CVE-2026-103043 anchorme through 3.0.8 Regular Expression Denial of Service
Attackers can cause denial of service in applications using the anchorme library by submitting crafted input that triggers catastrophic regex backtracking.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-103043?
CVE-2026-103043 is a high-severity denial of service vulnerability in alexcorvi anchorme, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
anchorme through 3.0.8 contains a regular expression denial of service vulnerability in the IPv6 host extraction regex due to catastrophic backtracking. Attackers can supply specially crafted input strings with repeated patterns to cause exponential regex engine backtracking, blocking the Node.js event loop and denying service to other requests.
Weakness: CWE-1333
Which versions are affected by CVE-2026-103043?
How do I fix CVE-2026-103043?
No fix has been published for CVE-2026-103043 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-103043 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-103043 exists.
Sources
Also known as GHSA-phc2-88rx-x2mp.