CVE-2021-4241phpservermon User.php setUserLoggedIn predictable algorithm in random number generator
- 2.6LowCVSS base score
- 1.0%Exploitation in 30 daysEPSS · top 36% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A vulnerability, which was classified as problematic, was found in phpservermon. Affected is the function setUserLoggedIn of the file src/psm/Service/User.php. The manipulation leads to use of predictable algorithm in random number generator. The exploit has been disclosed to the public and may be used. The name of the patch is bb10a5f3c68527c58073258cb12446782d223bc3. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-213744.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
Published
- 2 years later
· 2 years later
Record updated
- 19 months later
· 19 months later
EPSS rose above 1%
0.85% → 1.0%
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 3.1 | Low2.6 | CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 1.0% · top 36% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.6.
Affected products
- affected n/a
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistphpservermon/phpservermonGHSA-hc4j-7mqg-cxjj (opens in a new tab)
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2022-7360 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-hc4j-7mqg-cxjj (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-4241)Record last updated .