CVE-2026-88899

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.80% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 56.6% of scored records. A rank, not a probability.

NVD base score

9.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-09-11.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-09-10 15:28Z1 MO AGO

Last updated

2026-09-11 20:33Z1 MO AGO

Reserved

2026-09-10

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Critical (CVSS 9.3)

CNA CVSS vector

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

Weaknesses

• CWE-73External Control of File Name or PathBase

Data version

5.2

Document digest

2f3218424cc4d1fa1df1c2e16d50632788054e1a9eec2e78c962f9d96c013594

• github.comGitHub Security Advisory (GHSA-9h2q-r9fh-f98w)https://github.com/knowns-dev/knowns/security/advisories/GHSA-9h2q-r9fh-f98wvendor-advisory
• github.comhttps://github.com/knowns-dev/knowns/blob/v0.30.0/internal/server/server.go#L1283-L1296technical-description
• github.comhttps://github.com/knowns-dev/knowns/commit/37db0561b37b48b8bd035a417d7f1da6258ae657patch
• github.comknowns v0.31.0 Release Noteshttps://github.com/knowns-dev/knowns/releases/tag/v0.31.0release-notes
• www.vulncheck.comVulnCheck Advisory: knowns before 0.31.0 External Control of Agent Working Directory via x-opencode-directory Headerhttps://www.vulncheck.com/advisories/knowns-before-0.31.0-external-control-of-agent-working-directory-via-x-opencode-directory-headerthird-party-advisory