CVE-2026-104454

YesWiki before 4.6.7 contains an algorithmic-complexity denial of service in the wakka.php formatter due to an O(n^2) markdown-link regex. Unauthenticated attackers can submit a small crafted body of bracket characters to the page-edit preview endpoint to pin PHP-FPM workers and saturate the pool.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/YesWiki/yeswiki/security/advisories/GHSA-gf57-wg5m-h34q
https://www.vulncheck.com/advisories/yeswiki-before-4.6.7-redos-via-wakka-php-edit-preview-endpoint
https://github.com/YesWiki/yeswiki/security/advisories/GHSA-gf57-wg5m-h34q

Configurations

No configuration.

History

02 Oct 2026, 15:17

Type	Values Removed	Values Added
References	~~() https://github.com/YesWiki/yeswiki/security/advisories/GHSA-gf57-wg5m-h34q -~~	() https://github.com/YesWiki/yeswiki/security/advisories/GHSA-gf57-wg5m-h34q -

02 Oct 2026, 12:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 12:17

Updated : 2026-10-02 15:17

NVD link : CVE-2026-104454

Mitre link : CVE-2026-104454

CVE.ORG link : CVE-2026-104454

JSON object : View

Products Affected

No product.

CWE

CWE-1333

Inefficient Regular Expression Complexity

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