Seacms 11.1 - 'checkuser' Stored XSS

published 2026-01-25 9mo ago modified 2026-06-17 4mo ago also EUVD-2026-4635

cvss: 6.1; 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 20%
public exploits: 0; none known

SeaCMS 11.1 contains a stored cross-site scripting vulnerability in the checkuser parameter of the admin settings page. Attackers can inject malicious JavaScript payloads that will execute in users' browsers when the page is loaded.

Is CVE-2020-36932 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 9mo ago (2026-01-26)

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

exploit-db.com https://www.exploit-db.com/exploits/49251 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
CNA	3.1	6.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/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

Seacms Seacms

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

exploit-db.com /exploits/49251
exploit, vdb-entry
seacms.net /
product
vulncheck.com /advisories/seacms-checkuser-stored-xss
third-party-advisory

Sources

CVE List CVE-2020-36932
NVD CVE-2020-36932

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.

json all entries feed