Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Copier versions 9.5.0 up to 9.15.1 are affected. A trusted-prefix entry in the trust setting can be bypassed with ".." path segments, so a template that appears to be under a trusted location but actually resolves elsewhere runs its tasks without the trust prompt. An attacker who controls a template URL, such as via a project's answers file during copier update, could execute arbitrary commands. Upgrade to copier 9.15.2, which fixes this.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.8 | High | 4.0 | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0026, the 18th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:10 UTC First seen by agentprime
- 31 Oct 2026, 14:10 UTC Confirmed by OSV