CVE-2026-82601Public exploitNetwork attack vectorHinoki check available

Reflected XSS via unescaped errtxt output

Published Aug 31, 2026 · Updated Aug 31, 2026

Reflected XSS in /err.php in SeaCMS 13.0 through 13.6 allows remote attackers to execute script through a crafted errtxt value. The handler places errtxt inside a textarea without HTML escaping, so a closing tag can break out and introduce active markup. Exploitation requires a user to open a crafted URL, after which attacker-supplied script runs in that user's browser context.

CVSS severity4.3
Medium
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Reflected XSS in /err.php in SeaCMS 13.0 through 13.6 allows remote attackers to execute script through a crafted errtxt value. The handler places errtxt inside a textarea without HTML escaping, so a closing tag can break out and introduce active markup. Exploitation requires a user to open a crafted URL, after which attacker-supplied script runs in that user's browser context.

The record

CVE
CVE-2026-82601
Published
Aug 31, 2026
Updated
Aug 31, 2026
Vendor
SeaCMS
Product
SeaCMS
Classifications
CWE-94, CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 31, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=13.0
  2. Affected versionversion=13.1
  3. Affected versionversion=13.2
  4. Affected versionversion=13.3
  5. Affected versionversion=13.4
  6. Affected versionversion=13.5
  7. Affected versionversion=13.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

SeaCMS · SeaCMSversion=13.0; version=13.1; version=13.2; version=13.3; version=13.4; version=13.5; version=13.6

Published CVSS scores

5.0VulDB CNAAV:N/AC:L/Au:N/C:N/I:P/A:N
4.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
2.1VulDB CNACVSS: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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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