Is league/commonmark 0.19 vulnerable?

Composer · 4 releases from 0.19.0 to 0.19.3 · latest league/commonmark is 2.10.7 · checked 1 Nov 2026

Yes: 3 known advisories

Yes. league/commonmark 0.19.3, the last 0.19 release, is affected by 3 known security advisories (3 high), including CVE-2026-86430, CVE-2026-71488, CVE-2024-58382. Upgrade to 2.9.1 or later to fix all of them.

Upgrade with:composer require league/commonmark:^2.9.1

Is your project affected?

Private repo? Upload its lockfile instead, or connect GitHub to check every repo.

Advisories affecting league/commonmark 0.19.3

  • HighCVE-2026-86430GHSA-j8pm-gj4c-rq4x1 Sept 2026

    league/commonmark: Denial of service via crafted code fences, reference links, and emphasis delimiters

    Affected
    >=0.6.0 <2.9.1
    Fixed in
    2.9.1
  • HighCVE-2026-71488GHSA-2q4p-g7hv-5rgv6 Aug 2026

    league/commonmark: Quadratic-time denial of service when parsing crafted Markdown

    Affected
    >=0.6.0 <2.9.0
    Fixed in
    2.9.0
  • HighCVE-2024-58382GHSA-c2pc-g5qf-rfrf9 Dec 2024

    league/commonmark's quadratic complexity bugs may lead to a denial of service

    Affected
    <2.6.0
    Fixed in
    2.6.0

Which of your client projects are still on league/commonmark 0.19?

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Other league/commonmark versions

Advisory data from OSV.dev (opens OSV.dev in a new tab), which includes the GitHub Advisory Database. Release list from the Composer registry. Refreshed daily.