Turms IM Server v0.10.0-SNAPSHOT and earlier contains a broken access control vulnerability in the user online status query functionality.

published 2025-12-19 10mo ago modified 2026-10-13 27d ago also EUVD-2025-204539

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits: 0; none known

Turms IM Server v0.10.0-SNAPSHOT and earlier contains a broken access control vulnerability in the user online status query functionality. The handleQueryUserOnlineStatusesRequest() method in UserServiceController.java allows any authenticated user to query the online status, device information, and login timestamps of arbitrary users without proper authorization checks.

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CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 10mo ago (2025-12-19)

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

github.com https://github.com/Xzzz111/public_cve_report/blob/main/CVE-2025-66911_report.md referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Classification

Weakness

CWE-639 Authorization Bypass Through User-Controlled Key
CWE-284 Improper Access Control

References

github.com /Xzzz111/public_cve_report/blob/main/CVE-2025-66911_report.md
exploit, third-party-advisory
github.com /turms-im/turms
product
github.com /turms-im/turms/blob/develop/turms-service/src/main/java/im/turms/service/domain/user/access/servicerequest/co
product

Sources

CVE List CVE-2025-66911
NVD CVE-2025-66911

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.