SeaCMS err.php cross site scripting

published 2026-08-31 2 mo ago modified 2026-08-31 2 mo ago also EUVD-2026-68310

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 39%
public exploits: 0; none known

A weakness has been identified in SeaCMS up to 13.6. This affects an unknown part of the file /err.php. Executing a manipulation of the argument errtxt can lead to cross site scripting. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-31)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/T-Chachamaru/seacms-13.6-security-advisories/blob/a084a3e573240d54860153321df271280daec262/c-007-errtxt-reflected-xss.md referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	3.0	4.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N/E:POC/RL:ND/RC:UR
CNA	4.0	2.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
CNA	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:P/A:N

Affected products

n/a SeaCMS

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-94 Improper Control of Generation of Code

References

github.com /T-Chachamaru/seacms-13.6-security-advisories/blob/a084a3e573240d54860153321df271280daec262/c-007-errtxt-refle
exploit
vuldb.com /vuln/397103
vdb-entry, technical-description
vuldb.com /vuln/397103/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-82601
third-party-advisory
vuldb.com /submit/892786
third-party-advisory

Sources

CVE List CVE-2026-82601
NVD CVE-2026-82601

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