CVEvulnerability

CVE-2026-33347

6.3 MEDIUM Published 2026-03-24 Modified 2026-06-17 Official page ↗
Status
Analyzed
Published
2026-03-24
Last modified
2026-06-17
Assigner
[email protected]
CVSS 4.0 ([email protected])
6.3 MEDIUM — CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/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
CVSS 3.1 ([email protected])
6.1 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weaknesses
CWE-185, CWE-79, CWE-918

Description

league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.

Affected configurations

• thephpleague commonmark (>= 2.3.0 < 2.8.2)

Related

Weakness · CWE (3)

  • CWE-185 Incorrect Regular Expression weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness
  • CWE-918 Server-Side Request Forgery weakness

References