CVE-2026-89035: critical vulnerability in MikroTik RouterOS
MikroTik RouterOS 7.24.5 WebFig Session Token Replay Authentication Bypass
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 0.3%
from disclosure to weapon6 days
Published on NVDOct 21
1st PoC+6d
MikroTik RouterOS through 7.24.5 contains a session token replay vulnerability in the WebFig interface that allows attackers to bypass authentication by replaying captured session tokens across new ECDH sessions. The makeSessionKey function in libucrypto.so generates tokens using fixed salts without incorporating channel-specific or session-specific input, and the user service validates tokens against the login store without verifying channel context, enabling stolen tokens to grant persistent administrative access until the token store is explicitly cleared. This vulnerability extends the impact of CVE-2025-61481, which identified the underlying transport-layer exposure without a corresponding fix.
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Affected products
MikroTik · RouterOSpublic PoCs found — 2
githubgithub.com/emirwtz/CVE-2026-89035★ 0githubgithub.com/mehmet-emir-eroglu/CVE-2026-89035★ 0⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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