Calif Blog
blog.calif.io · Company blog · on HN since 2023
Calif, a security firm, publishes vulnerability research, exploit write-ups, and reverse engineering, including AI-assisted bug finding.
What HN saysHN commenters link it for the write-up of Claude writing a FreeBSD kernel exploit, including prompts, and for its macOS kernel exploit work.
28HN people shared it
6linked it in comments
28stories submitted
120story points
3 months agolast shared
2023people per year2026
Most-shared posts
- 1Mad Bugs: Claude Wrote a Full FreeBSD Remote Kernel RCE with Root Shell5 people · 5 points · first shared 2026 · 1 comments on HN
- 2Mad Bugs: Vim vs. Emacs vs. Claude4 people · 30 points · first shared 2026 · 16 comments on HN
- 3(Reverse Engineering) Apple Internals: Swift in the Kernel4 people · 10 points · first shared 2026 · discussion on HN
- 4First public macOS kernel memory corruption exploit on Apple M53 people · 10 points · first shared 2026 · 2 comments on HN
- 5Squidbleed (CVE-2026-47729)3 people · 7 points · first shared 2026 · discussion on HN
- 6Privilege Escalation in AWS Elastic Kubernetes Service2 people · 2 points · first shared 2023 · discussion on HN
- 7An AI Audit of FreeBSD2 people · 2 points · first shared 2026 · discussion on HN
- 8Dissecting LockBit v3 Ransomware1 people · 36 points · first shared 2024 · 5 comments on HN
- 9Even "cat readme.txt" is not safe1 people · 4 points · first shared 2026 · discussion on HN
- 10Codex Hacked a Samsung TV1 people · 3 points · first shared 2026 · discussion on HN
- 11A Race Within a Race: Exploiting CVE-2025-38617 in Linux Packet Sockets1 people · 3 points · first shared 2026 · discussion on HN
- 12How to format a ciphertext1 people · 3 points · first shared 2026 · discussion on HN
- 13OOBdump: Relocation Oriented Programming: Arbitrary code execution in objdump -g1 people · 2 points · first shared 2026 · discussion on HN
- 14Wormable Substack XSS1 people · 1 points · first shared 2024 · 1 comments on HN
- 15Codex Discovered a Hidden HTTP/2 Bomb1 people · 1 points · first shared 2026 · discussion on HN
What HN people wrote when they linked it
mtlynch · 2026-05-03
Worth noting that at this point, it's still somewhat trivial to find exploitable remote code execution bugs in Ladybird using AI tools.[0]
The userbase of Ladybug users is so small that it's probably not worth the attackers' time, but keep in mind that it's an enormous step down in security from the mainstream browsers who are actively searching for bugs using the latest tools and paying bug bounties on external reports.
[0] https://blog.calif.io/p/mad-bugs-rce-in-ladybird
cryptbe · 2026-05-26
Oh hey, this is our work! We helped Anthropic analyze and report this bug.
For the record, this bug has nothing to do with our recent MIE attack [1] [2], which exploited two different kernel bugs. Our bugs are not fixed yet.
[1] https://blog.calif.io/p/first-public-kernel-memory-corruption
[2] https://news.ycombinator.com/item?id=48139219
adamckay · 2026-05-23
Calif.io have access to Mythos Preview which they've used to find a macOS kernel memory corruption exploit on Apple M5: https://blog.calif.io/p/first-public-kernel-memory-corruption
It's probably the right approach to onboard a few independent security companies and task them with reviewing multiple OSS projects than it is to onboard each project individually.
tln · 2026-04-01
Or even better, the blog post.
https://blog.calif.io/p/mad-bugs-claude-wrote-a-full-freebsd
But I found the exploit writeup pretty interesting
tptacek · 2026-04-01
Calif (Thai Duong's firm) did a writeup on this, which should probably be the link here; it includes the prompts they used:
https://blog.calif.io/p/mad-bugs-claude-wrote-a-full-freebsd
A reminder: this bug was also found by Claude (specifically, by Nicholas Carlini at Anthropic).
kurtoid · 2026-03-31
Claimed to have been discovered with/by Claude: https://blog.calif.io/p/mad-bugs-vim-vs-emacs-vs-claude