CVE-2026-119660
MuseBot before 2.0.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge admin sessions by using the hard-coded default session_key 'muse_bot_session_key'.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.52%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
MuseBot before 2.0.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge admin sessions by using the hard-coded default session_key 'muse_bot_session_key'. Attackers can sign a MuseBot-session cookie carrying a user_id to gain full administrative access, reading password hashes, chat records, and bot configuration, and stopping bots.
- CVSS 4.0
- 9.3 CRITICALCVSS: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/M
- EPSS
- 0.52% probability · 44th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-1394
- Source
- disclosure@vulncheck.com
EPSS moved from 0.5% on 31 October 2026 to 0.5% on 3 November 2026.
References
- https://github.com/yincongcyincong/MuseBot
- https://github.com/yincongcyincong/MuseBot/blob/v1.0.42/admin/conf/conf.go#L28
- https://github.com/yincongcyincong/MuseBot/blob/v1.0.42/admin/controller/login.go#L19-L88
- https://github.com/yincongcyincong/MuseBot/commit/139f6158b50283b983d76976f593a3a09a064681
- https://github.com/yincongcyincong/MuseBot/commit/3e64518948fe7037058f07ef987d35216c3f0cae
- https://github.com/yincongcyincong/MuseBot/issues/61
- https://hackmd.io/@hieuPenguinnn/musebot-admin-default-session-key-auth-bypass
- https://www.vulncheck.com/advisories/musebot-before-2.0.0-authentication-bypass-via-hard-coded-session-key
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.