Vulnerability · Published Oct 30, 2026 · Assigned by VulnCheck

CVE-2026-119660MuseBot before 2.0.0 Authentication Bypass via Hard-Coded Session Key

Critical 9.8

In plain English

A critical-severity security flaw in MuseBot from yincongcyincong. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical

Exploit odds (30 days)0.5%top 55.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
yincongcyincong	MuseBot	0 – before 2.0.0

Weakness: CWE-1394 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

https://github.com/yincongcyincong/MuseBot/issues/61 issue-tracking
https://github.com/yincongcyincong/MuseBot/commit/3e64518948fe7037058f07ef987d35216c3f0cae patch
https://github.com/yincongcyincong/MuseBot/commit/139f6158b50283b983d76976f593a3a09a064681 patch
https://github.com/yincongcyincong/MuseBot/blob/v1.0.42/admin/conf/conf.go#L28 technical-description
https://github.com/yincongcyincong/MuseBot/blob/v1.0.42/admin/controller/login.go#L19-L88 technical-description
https://hackmd.io/@hieuPenguinnn/musebot-admin-default-session-key-auth-bypass third-party-advisory
https://github.com/yincongcyincong/MuseBot product
VulnCheck Advisory: MuseBot before 2.0.0 Authentication Bypass via Hard-Coded Session Key third-party-advisory