CVE-2026-88899
criticalknowns versions before 0.31.0 fail to properly validate the x-opencode-directory request header in the /api/opencode proxy endpoint.
knowns versions before 0.31.0 fail to properly validate the x-opencode-directory request header in the /api/opencode proxy endpoint. Remote attackers can supply arbitrary directory paths to execute file operations outside the project root on the host system.
CVSS
9.8
9.8 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Severity source: NVD CVSS v3.1 (disclosure@vulncheck.com)
Timeline (UTC)
Published: 2026-09-10 16:18
Modified: 2026-09-11 21:17
NVD status: Deferred
Last synced 2 days ago
Verified against the source API 2026-10-27 06:52 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296 disclosure@vulncheck.com
- https://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657 disclosure@vulncheck.com
- https://github.com/knowns-dev/knowns/releases/tag/v0.31.0 disclosure@vulncheck.com
- https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98w disclosure@vulncheck.com
- https://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-workin... disclosure@vulncheck.com
Data sources
NVD CVE API 2.0 — fetched 2026-10-27 06:52 UTC · record ↗