GitLab critical patch release
docs.gitlab.com
docs.gitlab.com
This is the best overview I found: https://lilting.ch/en/articles/gitlab-cve-2026-110264-org-mo...
The bottom line: this is an issue in Ruby's regex engine, which was fixed in April and backported recently. [1]
Everyone running applications where attacker-controlled input might find its way (unescaped) into Ruby regexes is vulnerable to remote code execution.
… Or is the GitLab/onigmo bug about failing to escape regex input?
Big malicious entities always had more investments in this than random open source projects.
The last few months seem to have been a lot more imunder control with also the frontier labs more warning of "what happens when Mythos-class model get in the hands of everyone" than that actually becoming reality. Now, it appears to be actuually turning into reality.
I'd say, the single worst security news day for now
It's over. Cybersecurity is now Yugioh, where the lifepoints is your token budget.
Can I get that in writing?
As we speak more slop is added to the pile, far more than can reasonably be reviewed and a lot of that code will be insecure.
It needs to be designed to be secure.
[^] of course I'm hyperbolic here, it does still need to be reviewed – I just mean, review doesn't matter as much as choosing a secure design, where certain bugs just can not or will not happen.
The attack needs no authentication — only one public project that can hold the .org payload.
So probably not vulnerable if no public projects exist - ie self hosted has an needs auth for everything mode.Is this similar?
I wonder why gitlab even has its own regex compiler. Or is this a vulnerability in an underlying library or programming language?
after updating a pop-up still shows:
"You are currently on version 19.5.1! We strongly recommend upgrading your GitLab installation immediately."
while 19.5.1 should be the latest and fixed version
But I also updated pretty early.
Coincidentally, there is also a (non-embargoed) musl libc CVE published today involving integer overflow in its regex compiler: https://www.openwall.com/lists/musl/2026/10/21/1
Perhaps that is the underlying bug, or a similar one turned up by the same security research?
GitLab has remediated an issue that, under certain conditions, could have allowed an unauthenticated user to execute arbitrary code on the GitLab server due to integer overflow when compiling a specially crafted regular expression. (...)
CVSS 10.0 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)
Here, CVSS 10.0 means arbitrary remote code execution.
My experience has been that CVSS has really just not been very informative or well-calibrated to risk.
Might you perchance be exaggerating?
CVSS is like the Pitchfork Music ratings scale. It communicates false precision, and it's easy to point to places where that precision misleads (D-plan's "Emergency & I" is not better than every Yo La Tengo album).
For example if I cry wolf 50% of the time, but 100% of the times there's a wolf I cry wolf. Then no matter what the frequency of wolf sightings are, my crying wolf carries some information (unless there's always a wolf). Assume there's a wolf 1% of the nights, then I will cry wolf 50% of the time, and you only need to check for a wolf 50% of the nights rather than 100%.
It's worth noting that there's still technically signal even if I sometimes miss a wolf, even if you may choose to ignore that signal in order to pursue 100% accuracy yourself.
CVSS is good, it's better than nothing.
Any suggestions folks, not even my terminally online self can handle all of these.
But it's a lot better than having things live on the open internet!
Also looking at those old C++ services a whole lot differently now.