Possibility to generate a session for any user via the "ex:action" parameter after obtaining access to the JWT key

published 2025-08-27 14 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-27774

cvss: 8.8; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.1%; EPSS 0.1% chance of exploitation in 30 days, percentile 0%
public exploits: 0; none known

An insufficiently secured internal function allows session generation for arbitrary users. The decodeParam function checks the JWT but does not verify which signing algorithm was used. As a result, an attacker can use the "ex:action" parameter in the VerifyUserByThrustedService function to generate a session for any user.

Patch / fix

fixed in 1

CGM CGM CLININET 2025.MS2

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 14 mo ago (2025-08-27)

Exploit prediction

0.08% chance of exploitation in the next 30 days, higher than 0% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.8	CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA	4.0	8.8	CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

CGM CGM CLININET

Classification

Weakness

CWE-912 Hidden Functionality
CWE-347 Improper Verification of Cryptographic Signature

References

cert.pl /en/posts/2025/08/CVE-2025-2313/

Sources

CVE List CVE-2025-30064
NVD CVE-2025-30064

Fencer Vulns 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.

Summary