CVE-2026-105829

Publication date 13 October 2026

Last updated 13 October 2026

Ubuntu priority

Cvss 3 Severity Score

Description

League CommonMark from 1.3.0 before 2.10.2 contains a cross-site scripting vulnerability that allows users posting Markdown to bypass the DisallowedRawHtml extension by ending raw HTML with a bare disallowed tag name. Attackers can place a lone <script or <iframe line followed by a block supplying attributes like src or onload, executing stored scripts in viewers' browsers under default GFM settings.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
php-league-commonmark	26.04 LTS resolute	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation

Severity score breakdown

CVSS version:

Base score 5.3 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Attack requirements	None
Privileges required	None
User interaction	Passive
Vulnerable system - Confidentiality impact	Low
Vulnerable system - Integrity impact	Low
Vulnerable system - Availability impact	None
Subsequent system - Confidentiality impact	Low
Subsequent system - Integrity impact	Low
Subsequent system - Availability impact	None

Scores

Parameter	Value
Base score	5.3 · Medium
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Base score 6.1 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Changed
Confidentiality impact	Low
Integrity impact	Low
Availability impact	None

Scores

Parameter	Value
Base score	6.1 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVE-2026-105829

Cvss 3 Severity Score

Description

Status

Severity score breakdown

References

Other references

Access our resources on patching vulnerabilities