CVE-2026-6729

HKUDS OpenHarness prior to PR #159 remediation contains a session key derivation vulnerability that allows authenticated participants in shared chats or threads to hijack other users' sessions by exploiting a shared ohmo session key that lacks sender identity verification. Attackers can reuse another user's conversation state and replace or interrupt their active tasks by colliding into the same session boundary through the shared chat or thread scope.

CVSS 4.0

5.3CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

CVSS 3.1

7.6CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L

EPSS

0.2% chance of exploitation in the next 30 days; higher than 9% of CVEs (scores of 2026-10-25)

CWE

CWE-287

Published

2026-04-20

Modified

2026-10-25

Record from

the NVD, synced 2026-10-25

Affected

• hkuds:openharness

References

• https://github.com/HKUDS/OpenHarness/commit/3186851c479ee714a9bb9aa6cd77017db7e589e2
• https://github.com/HKUDS/OpenHarness/pull/159
• https://www.vulncheck.com/advisories/hkuds-openharness-session-key-collision-privilege-escalation
• https://github.com/HKUDS/OpenHarness/pull/159

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