CVE-2026-88899

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 v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296
https://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657
https://github.com/knowns-dev/knowns/releases/tag/v0.31.0
https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98w
https://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-working-directory-via-x-opencode-directory-header

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-10 16:18

Updated : 2026-09-11 21:17

NVD link : CVE-2026-88899

Mitre link : CVE-2026-88899

CVE.ORG link : CVE-2026-88899

JSON object : View

Products Affected

No product.

CWE

CWE-73

External Control of File Name or Path

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