CVE-2026-88899criticalCWE-73

CVE-2026-88899: critical vulnerability in knowns-dev knowns

knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Header

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48Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 9.3epss 0.8%
from disclosure to weapon4 days
Published on NVDSep 10
1st PoC+4d
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
knowns-dev · knowns
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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