High severity · published Oct 21, 2026
CVE-2026-89035
MikroTik RouterOS 7.24.5 WebFig Session Token Replay Authentication Bypass
New
7.4
CVSS
0.3%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RO
RouterOS · MikroTik
through 7.23.6; 7.24.0 through 7.24.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-89035
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-89035
www.vulncheck.com
https://www.vulncheck.com/advisories/mikrotik-routeros-webfig-session-token-replay-authentication-bypass
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