Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Fission versions before 1.23.0 pass the Environment builder command straight to exec without validating the executable, so a user who can create or update Environment objects in a namespace watched by buildermgr can run arbitrary executables inside the builder pod. That pod can read and write the shared package volume, which bounds the impact to that namespace's package contents. Upgrade to 1.23.0, which validates the build command path. Until then, restrict who can create or modify Environment objects and audit existing builder command values for anything other than /build.
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 |
|---|---|---|---|---|
| 6.9 | Medium | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0036, the 30th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 15:07 UTC First seen by agentprime
- 31 Oct 2026, 15:07 UTC Confirmed by OSV