VulnerabilityDeferred

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.

MEDIUM 6.9EPSS 0.40%

Does this matter?

Lower severity and a low EPSS score (0.40%). Track it; it rarely justifies an emergency change on its own.

Description

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 4.0: 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.40% probability · 34th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-1333
Source: disclosure@vulncheck.com

EPSS trend

EPSS moved from 0.4% on 3 October 2026 to 0.4% on 26 October 2026.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.