Alex Rebert @ayper
Security @ Google. Previously co-founder of @ForAllSecure. Opinions here are my own. @[email protected] Pittsburgh Joined August 2008-
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Can we translate all C to Rust? The susceptibility of C to memory corruption has long been a cybersecurity pain point, and coding agents can free us of it. Read on for my recent experiments in this space, and apt & docker repos that you can pull rust-converted libraries from!
Hardening the C++ Standard Library at massive scale. A look at increasing memory safety with libc++ hardening — a collaborative paper from engineers at Apple and Google. The results have been impressive: at Google the team discovered and fixed 1000+ bugs as hardening was enabled. queue.acm.org/detail.cfm?id=…
We're joining forces with industry & academia to call for memory safety standardization: security.googleblog.com/2025/02/securi…. It's a recognition that memory unsafety is no longer a niche technical problem but a societal one, impacting everything from national security to personal privacy.
🛡️Want to help make the open source world safer and earn up to $45k 💰? We've revamped our Patch Rewards Program, extending its scope and increasing rewards for security patches – with a particular focus on memory safety, including bonus multipliers! bughunters.google.com/blog/527306491…
Celebrating 15 years of password hacking 💻 🔑, Swiss Army knives (and sometimes even chainsaws or swords) included! 😲 Discover how Google's security teams turn employee farewells into security tests. bughunters.google.com/blog/635526578…
@kupiakos Oops, I missed this. OOB accesses terminate the program immediately. See libcxx.llvm.org/Hardening.html…
Excited to share our latest post on memory safety! We're tackling spatial safety in our massive C++ codebase by hardening libc++ *by default*. It adds bounds checks to things like std::vector, preventing a fair bit of out-of-bounds vulnerabilities: security.googleblog.com/2024/11/retrof…
Bounds-checking in C++: so people ask if the .3% overhead is real. It's not just a benchmark result, we got this through our Google-Wide profiling, that gives us the live insights from DCs. This surprised us too as it was much cheaper than we thought research.google/pubs/google-wi…
Excited to share our latest post on memory safety! We're tackling spatial safety in our massive C++ codebase by hardening libc++ *by default*. It adds bounds checks to things like std::vector, preventing a fair bit of out-of-bounds vulnerabilities: security.googleblog.com/2024/11/retrof…
@RoseSilicon The blog post is mostly about server-side code, where it was recently rolled out. But chrome also has it on since 2022.
@seanbax In particular, you can see the enabled checks with: - github.com/search?q=repo%… - github.com/search?q=repo%…
@seanbax That's right! Hardening does a few more things than just bounds checking: empty optional checks, sanity checks on sizes, sort ... I'm not aware of a comprehensive list -- I usually grep for the 2 enabled libc++ macros defined in github.com/llvm/llvm-proj…
The best part? It's incredibly cost-effective, with an average performance overhead of just 0.30%. So there's really no reason not to do it if you're running C++ code :)
This improves spatial memory safety across Google's services, including performance-critical components of Search, Gmail, Drive, YouTube, and Maps. We've already seen it disrupt a red team exercise, reduce segfaults by 30%, and improve code correctness.
The dedication and hard work has payed off: "for hundreds of complex web applications that are built on Google’s hardened and safe-by-design frameworks, we've averaged less than one XSS report per year in total" (see page 9 of the whitepaper).
Secure by design takes dedication and years of hard work to get the balance right between velocity and safety. Read a bit about @Google’s commitment and journey in our new white paper. Humbled to work with the professionals that make this happen everyday. blog.google/technology/saf…
Percentage of codebase that's memory-safe 📈, memory-safety vulns 📉, EVEN IF YOU KEEP ADDING LINES OF C 🤯
NEW EPISODE! You may not be rewriting the world in Rust, but if you walk like the Android team, you'll drive down your memory-unsafety vulnerabilities more than 2X below the industry average over time! 🎉 securitycryptographywhatever.com/2024/10/15/a-l… youtu.be/WL4CgVI6p9g
Excited to share Google's memory safety strategy! We're working to build safer software by migrating to memory-safe languages like Rust as well as hardening our existing C++: security.googleblog.com/2024/10/safer-…. We'll be sharing more details in upcoming posts.
Google CVR is doing incredible vulnerability research.
Learn how Google CVR could have potentially exfiltrated Gemini 1.0 Pro before launch last year. We describe the vulnz, the fix, and tips for bughunters. Also, shout-out to @epereiralopez for teaming up to adapt this work to another cloud provider. bughunters.google.com/blog/567986357…
@lauriewired Our team at Google just published a blog post with related findings on the half-life of vulnerabilities and how prioritizing safety in new code can dramatically improve overall security: security.googleblog.com/2024/09/elimin…
@sephr The simulated results, which closely match the empirical data in Android, did not assume any prioritization. So prioritization does not appear to explain the effectiveness of this strategy, although it may explain why the Android results outperformed the simulation.
The drop in Android's memory safety vulnerabilities is astonishing. It's counterintuitive, but prioritizing memory-safe languages in new code quickly reduces memory-safety risks. Once we turn off the tap of new vulnerabilities, they start decreasing exponentially.
I’m super excited about this blogpost. The approach is so counterintuitive, and yet the results are so much better than anything else that we’ve tried for memory safety. We finally understand why. security.googleblog.com/2024/09/elimin…
@sephr Because the risk reduction far outweighs what one would expect from the % of memory-safe code. Android has *more* memory-unsafe code than it did in 2019, and yet, it has almost an order of magnitude fewer memory safety vulns.
Brendan Dolan-Gavitt @moyix
33K Followers 6K Following Building offsec agents: https://t.co/G9EtnC2Gl3 PGP https://t.co/3WXr0RfRkv
Marcel Böhme👨�... @mboehme_
7K Followers 1K Following Software Security Group @maxplanckpress PhD @NUSComputing, Singapore Research Group: https://t.co/BRnFNNh6d9
Oliver Chang @halbecaf
2K Followers 147 Following https://t.co/bmyDmTlFKv Senior Staff Eng @ Google DeepMind. Former: founder of https://t.co/K575lba4tt, lead/co-founder for OSS-Fuzz.
Abhishek Arya @infernosec
5K Followers 185 Following Principal Engineer, AI Security at Google. Opinions are my own.
David Korczynski @Davkorcz
1K Followers 257 Following researcher @ADALogics | Software security, fuzzing, vulnerability analysis, AI, open source. | CS PhD from @CompSciOxford
Dmitry Vyukov @dvyukov
9K Followers 387 Following I tweet about fuzzing, bugs, sanitizers, security, hardening, kernels, syzkaller, Go, performance, concurrency, lock-free algorithms.
Halvar Flake @halvarflake
45K Followers 3K Following Choose disfavour where obedience does not bring honour. I do math. And was once asked by R. Morris Sr. : "For whom?" @[email protected]
Khaled Yakdan @KhaledYakdan
538 Followers 190 Following Co-founder @CI_FUZZ. Fuzzing/Vulnerability Research, Reverse Engineering, Malware Analysis.
Jonathan Metzman @metzmanj
2K Followers 627 Following I do fuzzing on Google's Open Source Security Team. I work on OSS-Fuzz/ClusterFuzz/FuzzBench. Speaking on behalf of myself, not my employer.
Richard Johnson @richinseattle
19K Followers 3K Following Computer Security, Reverse Engineering, and Fuzzing; Training & Publications @ https://t.co/mloVP6rPB7; hacking the planet since 1995; Undercurrents BOFH
Kostya Serebryany @kayseesee
4K Followers 569 Following Program analysis, simulators, bug detectors. Fuzzing software and hardware. Views are my own. Tweets are not only about tech.
FuzzingLabs @FuzzingLabs
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Harrison Green @hgarrereyn
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Andy Nguyen @theflow0
69K Followers 447 Following The opinions stated here are my own, not those of my company.
Mihai Maruseac @mihaimaruseac
3K Followers 2K Following Building AGI with security and privacy at @openai. Previously: @google (model-signing, GUAC, @tensorflow), LeapYear (Haskell, ML, DP)
Crispin Cowan 🇺�... @CrispinCowan0
2K Followers 3K Following Heretical investor: Long-only momentum compounding, CAGR maximalist Infosec legacy: Stack canaries, LSM, AppArmor, AppContainer Erdős 3 Pronoun: "Doctor"
KT @koczkatamas
4K Followers 927 Following Security Engineer @ Google (personal account, opinions are my own!). ex-Tresorit. Ex-captain of @SpamAndHex CTF team.
Thuan Pham @thuanpv_
2K Followers 887 Following Senior Lecturer in Cyber Secutity at @UniMelb & ARC DECRA Fellow. Prev @MonashInfotech & @NUSComputing. (Fuzz) Testing enthusiast. Tweets are my own.
haroon meer @haroonmeer
17K Followers 3K Following Security Geek at Thinkst. We build https://t.co/Sv6Gp3sG6b
Newton Cheng @newton_cheng
2K Followers 255 Following Frontier Red Team at @AnthropicAI | Physics PhD from @UCBerkeley
Mary wade @mwade33
2 Followers 530 Following
Henry Yates @HPY
925 Followers 5K Following Co-founder https://t.co/Jp7EdOiyNv Founder https://t.co/TckwDqeOrV Founder https://t.co/AiDU12dsys
ciphwall @ciphwall
0 Followers 180 Following
Adam Eehan @AdamE2EE
0 Followers 17 Following
Ivan M @med_1v
1 Followers 3K Following
Jevin Sweval @jevinskie
2K Followers 5K Following Fuck Elon Musk and his fascist & racist friends This account is archived. Find me elsewhere. https://t.co/aPN2y5oggJ
Helen Audrey @HelenAudre25742
1 Followers 40 Following
Aaron Klotz 🇨🇦�... @dblohm7
665 Followers 3K Following Not the freelance tech writer. Seasoned hacker of software. Proud Canadian. Proud Albertan. Unabashed Zionist.
ACM Queue @ACMQueue
12K Followers 144 Following Online magazine of the Association for Computing Machinery
Johnny @Luckyrocky2028
250 Followers 7K Following Stay Hungry, Stay Foolish. Only those who are self-disciplined can attain true freedom.|No Politics.
Olivia @Olivia446od
17 Followers 996 Following
Claes Spett (.PrØÐi... @J3rge
7K Followers 693 Following Programmer | Exploit Dev | Reverse Engineering | Backdooring Everything I Break! - Author of Genocide.sys C2/Rootkit - 0xFFFFFFUCk
Endo0vx @endo0vx
2 Followers 164 Following
Yusuf M. Husayn @0xwaterblade
38 Followers 958 Following Cybersecurity Engineer | Red Teaming | Bug Hunter
Muhmd Nashaat @TheNetov
460 Followers 927 Following Electrical & Communications Engineering, Security Enthusiast, Self-learner
Piper @piperchester
307 Followers 2K Following Continually learning and undergoing maintenance. If not in codes, probably out doors.
Parsa @sighpaaa
11 Followers 4K Following
甲斐下英一 @kaishitaeiichi
406 Followers 2K Following 男。1975/10/01生まれ。フリーのITエンジニア。もう10年以上データ分析やデータ基盤などのシステムの開発、運用にたずさわっています。統計検定1級。
KYZRTXP @kyzrtxp
4 Followers 634 Following
Tiago Nascimento @vilard
19 Followers 149 Following
eymeteymet77 @eymet1
69 Followers 2K Following Digital creators, marketer and publishing end to end encrypted data and privacy policy keeper.
JackSidewinder @JackSidewinder
114 Followers 3K Following
dainel @dainel7906771
0 Followers 26 Following
Ahmet Hasircioglu @roxaxis
204 Followers 1K Following software developer, blockchain enthusiast, sci-fi lover, nintendo addict, big supporter of beer industry, husband, owned by two cats
Emmy Achi @achimlejit
41 Followers 1K Following I am a scout for Start Engine and I help get innovators, CEO'S and founder's onboard StartEngine's investor roundtable to acquire funding
Shoresh Archer @ShoreshArcher
9 Followers 535 Following Former lamb-shepherd(aka Berxvan) in Elegez/Ararat. SW Developer in the field of NFC, RFID, IoT, PROFINET, TSN.
Cvewhen? @cvewhen
442 Followers 2K Following just never thought i couldn't. presently cry/curse/stress/scream till the models obey @hacktronai
Iteractively @iteractively
21 Followers 1K Following
Daniel Moghimi @flowyroll
2K Followers 336 Following Senior Scientist @Google. Computer and Hardware Security. Tweets are mine and not my employer's. #downfall Previously: @UCSD @Qualcomm @WPI @TalosSecurity
比个心 @vbigthing
51 Followers 4K Following
hikalium @hikalium
14K Followers 1K Following Fully-stuck Operating System Software Engineer at Google ( ChromeOS ) / 早大情報理工←学芸大附高 / WasabiOS / https://t.co/2C4XlSy922 / Opinions are my own
Dylan Zhang @dylan_works_
1K Followers 6K Following Looking for Internships & Collab (Start-up's welcome!!) Modeling Language @UofIllinois CS PhD | SR @GoogleDeepMind | Ex. @MSFTResearch Intern
boyz @indahoodboyz
4 Followers 430 Following
Sajjad “JJ” Arsha... @sajjadium
1K Followers 245 Following Gmail/Web Security @Google, #GoogleCTF Organizer, @DEFCON Instructor
L0Psec @L0Psec
4K Followers 2K Following reverse engineer | arm64 :) | macOS/iOS | YouTube: https://t.co/VdHNCl0Qfl
Brendan Dolan-Gavitt @moyix
33K Followers 6K Following Building offsec agents: https://t.co/G9EtnC2Gl3 PGP https://t.co/3WXr0RfRkv
Marcel Böhme👨�... @mboehme_
7K Followers 1K Following Software Security Group @maxplanckpress PhD @NUSComputing, Singapore Research Group: https://t.co/BRnFNNh6d9
Oliver Chang @halbecaf
2K Followers 147 Following https://t.co/bmyDmTlFKv Senior Staff Eng @ Google DeepMind. Former: founder of https://t.co/K575lba4tt, lead/co-founder for OSS-Fuzz.
cts🌸 @gf_256
67K Followers 982 Following founder and hacker @zellic_io @v12sec @pb_ctf yt https://t.co/nlNai6iQCn
Abhishek Arya @infernosec
5K Followers 185 Following Principal Engineer, AI Security at Google. Opinions are my own.
chompie @chompie1337
88K Followers 1K Following hacker, exploit developer/weird machine mechanic head of X-Force Offensive Research (XOR) @IBM
David Korczynski @Davkorcz
1K Followers 257 Following researcher @ADALogics | Software security, fuzzing, vulnerability analysis, AI, open source. | CS PhD from @CompSciOxford
lcamtuf @lcamtuf
40K Followers 499 Following Substack: https://t.co/yFvmNisGW3 Homepage: https://t.co/iFAXZxCO5H
Dmitry Vyukov @dvyukov
9K Followers 387 Following I tweet about fuzzing, bugs, sanitizers, security, hardening, kernels, syzkaller, Go, performance, concurrency, lock-free algorithms.
chrisrohlf @chrisrohlf
11K Followers 926 Following Waging algorithmic warfare since 2003. Engineer, Researcher. MTS @ Anthropic, Non-Resident Research Fellow @CSETGeorgetown CyberAI
Julien Vanegue @jvanegue
6K Followers 984 Following CTO Office / Head of Infra & Security Research @Bloomberg. Interested in mathematical techniques for software, systems, and network analysis at world scale.
Halvar Flake @halvarflake
45K Followers 3K Following Choose disfavour where obedience does not bring honour. I do math. And was once asked by R. Morris Sr. : "For whom?" @[email protected]
Andrea Fioraldi @andreafioraldi
3K Followers 587 Following Cyber Response Italian Supercazzola Technology Officer at @mhackeroni Inc. Writing your favourite fuzz testing tools with @aflplusplus. Security researcher at
Maddie Stone @maddiestone
62K Followers 796 Following Security Researcher. Previously Google Project Zero and TAG | 0days all day. Love all things bytes, assembly, and glitter. she/her.
Mathias Payer @gannimo
8K Followers 383 Following Securitatis inquisitor and professor at @EPFL_en leading the #HexHive 🐝 group, focusing on system/software security. @[email protected] (he/him)
Ange @angealbertini
25K Followers 920 Following Reverse engineer, file formats expert. Corkami, CPS2Shock, PoC||GTFO, Sha1tered, Magika... Security engineer @ Google. He/him.
Khaled Yakdan @KhaledYakdan
538 Followers 190 Following Co-founder @CI_FUZZ. Fuzzing/Vulnerability Research, Reverse Engineering, Malware Analysis.
dmnk.bsky.social @domenuk
5K Followers 509 Following 【DΞCOMPILΞ NΣVΞR】 Android Red Team @google Fuzzing @aflplusplus CTF @enoflag (opinions my own)
Jonathan Metzman @metzmanj
2K Followers 627 Following I do fuzzing on Google's Open Source Security Team. I work on OSS-Fuzz/ClusterFuzz/FuzzBench. Speaking on behalf of myself, not my employer.
Sarah Young @_sarahyo
10K Followers 1K Following Security & AI stuff @microsoft | Co-host of @AzureSecPod | Mother of shibes | Mostly dogs, carbs & security posts | Opinions mine
Newton Cheng @newton_cheng
2K Followers 255 Following Frontier Red Team at @AnthropicAI | Physics PhD from @UCBerkeley
Calif @calif_io
5K Followers 30 Following We're https://t.co/KTEDnC2VUV. Join us to make the Internet safer for your mum and everyone else: https://t.co/eUFMLkW9t2.
Michael Niedermayer @michael__ni
2K Followers 93 Following
FFmpeg @FFmpeg
117K Followers 184 Following The universal multimedia toolkit. A diverse, community-driven project; posts are by individuals.
Raluca Ada Popa @ralucaadapopa
7K Followers 178 Following Head of Security and Privacy Research @ Google DeepMind. @UCBerkeley security professor. MIT PhD. Co-founder of @OpaqueSys, @imua & @PreVeil.
Sajjad “JJ” Arsha... @sajjadium
1K Followers 245 Following Gmail/Web Security @Google, #GoogleCTF Organizer, @DEFCON Instructor
David Roche @MountainRoche
24K Followers 2K Following Coach of runners on the trails, roads & track 🦖 Leadville 100 Mile course record holder 🧡 Check out the Some Work All Play podcast!
Xion @0x10n
5K Followers 129 Following CMU CSD PhD student | '24/'25 Top#0 Chrome Researcher | P2O Vancouver '24, TyphoonPWN '24/'25, DEFCON CTF 31-33, ... | PPP, KAIST GoN '18, @zer0pts
alyssa mastromonaco @AlyssaMastro44
133K Followers 3K Following jam maker. rescue cat mom. some days Nancy Drew, others Ramona Quimby. books, #hysteria, producer.
Cristina Cifuentes @criscifuentes
2K Followers 288 Following Latina, migrant, mother and wife, researcher, teacher, mentor, leader. Mother of decompilation
Ben L. Titzer @TitzerBL
2K Followers 346 Following Director of the WebAssembly Research Center at Carnegie Mellon University. Principal Researcher. Wasm co-founder. Former V8 engineer. Compilers!
Shane Miller @SkippersWif
1K Followers 1K Following CEO | Certified Autism Specialist | Ex-AWS, GEICO, CSC
Carl Smith @cffsmith
1K Followers 720 Following Security @Google; @FluxFingers/@Sauercl0ud; previously V8 Security, Intern {Project Zero, @XI_Research}. Personal account. https://t.co/w9zosKSHdh on Bluesky.
Calle Svensson @ZetaTwo
7K Followers 722 Following Security Engineer @ XTX. MSc in eng. physics & CompSci, dev & gamer. ❤️ music & long distance running. Wanna do a PhD sometime. Same U/N on all other sites
Will Harris @parityzero
4K Followers 801 Following Chrome Security gnome. I work on the sandbox and local data protection on Windows. @parityzero.99 on signal. Opinions here are my own!
Rep. Summer Lee @RepSummerLee
68K Followers 2K Following Representing Pennsylvania's 12th Congressional District. Member of @OversightDems and @EdWorkforceDems.
Jeff Geerling @geerlingguy
91K Followers 5K Following Father, author, developer, maker. Sometimes called "an inflammatory enigma". #stl #ansible #k8s #raspberrypi #crohns #ostomy
polict @polict_
1K Followers 268 Following The opinions stated here are my own, not those of my company.
Joseph Cox @josephfcox
91K Followers 3K Following Hacking/crime/privacy journalist. Author of DARK WIRE. Co-founder of @404mediaco. Signal: joseph.404 Email: [email protected]
Lukas Weichselbaum @we1x
2K Followers 505 Following Leading @Google's web security team. Opinions are my own. Bluesky: @webappsec.dev
Mark Griffin @seeinglogic
376 Followers 105 Following Dev/hacker | Improving human understanding of code | A picture's worth 1KLOC
Kinuko Yasuda @kinu
14K Followers 695 Following Principal Software Engineer @Google 🇩🇪 / Large scale AI, Safety, C++ / Opinions are my own @kinuko.bsky.soc https://t.co/6rTECc5OSx
b33f | 🇺🇦✊ @FuzzySec
33K Followers 1K Following 意志 / mobile research @ ▓▓▓▓▓ / Team 501 / ex IBM Capability Lead & FireEye TORE / I rewrite pointers and read memory / AI Psychoanalyst / Teaching @CalypsoLabs
Joshua J. Drake @jduck
27K Followers 2K Following Securing the future through modern technology. Founder and Software Security Specialist at @magnetitesec
Forrest Brazeal @forrestbrazeal
41K Followers 218 Following Purveyor of good tech things. prev. @google. PARADOX INC is out from Ballantine Jan 27! Preorder: https://t.co/c0zzUlbfS5
Pete Buttigieg @PeteButtigieg
3.8M Followers 3K Following Husband, dad, veteran, writer, and proud Midwesterner. 19th US Secretary of Transportation and former Mayor of South Bend.
nolen @itseieio
25K Followers 703 Following one million checkboxes/chessboards, https://t.co/rXQU7beXZU, https://t.co/qH1JodNJMM, etc. the internet can still be fun! alum recurse, jane street
TracketPacer @TracketPacer
67K Followers 408 Following 🚀 rockit network engineer | 👩🏼💻🛜professional wire gremlin | she/her (pronouns just to trigger u)
Will Crichton @tonofcrates
7K Followers 160 Following Cognitive engineer, assistant professor @BrownUniversity.
Tom 7 @tom7
8K Followers 359 Following lexicographic NES AIs, alphabetical star wars, video games, fonts, album-a-day, expert mode running, chiptune, programming languages, etc.
Sophia d’Antoine @Calaquendi44
3K Followers 123 Following Founder @Margin_Research, Hacker in Residence @ NYU, @RPISEC
Dr. Claire Le Goues @clegoues
3K Followers 1K Following Prof@SCS@CMU. https://t.co/fcjhKkZzHd Posting intermittently and guiltily.
Matt Lehman @obsecurus
789 Followers 1K Following Principal Investigator & AI Strategist | AIxCC Lead Architect (Opinions are my own)
DARPA @DARPA
281K Followers 389 Following Official account of the Defense Advanced Research Projects Agency. Follows/retweets/links do not = endorsement. Breakthrough technologies for national security.
Joshua Saxe @joshua_saxe
3K Followers 1K Following Now: building in stealth. Before: AI+cybersecurity at Meta. Way before: labor / community organizing, classical/jazz piano, hacking scene
Tristan Brindle @tristanbrindle
1K Followers 200 Following Computer guy. Recovering mathematician. Likes C++, for some reason.
Oege de Moor @oegerikus
7K Followers 598 Following CEO and founder of XBOW. Previously: Founder of GitHub Next, founder of GitHub Copilot, CEO and founder of Semmle (GitHub Advanced Security), prof at Oxford.
XBOW @Xbow
12K Followers 13 Following Bringing AI to offensive security by autonomously finding and exploiting web vulnerabilities. https://t.co/D5Mco1tAKe
Know Your Meme @knowyourmeme
667K Followers 388 Following Documenting all of internet culture. Trying to understand a meme? Tag us and we'll give you the scoop Check out our website! https://t.co/nkGvDMAqa6
Dmitri Alperovitch @DAlperovitch
203K Followers 2K Following Geopolitics/NatSec, Russia, China, Cyber. Chairman @SilveradoPolicy; Author WorldOnTheBrink; Host @GeopolDecanted; Founder @alperovitch; Co-Founder @CrowdStrike

























