Mistune plugins/formatting: quadratic-time parsing on long runs of `~~x~~`, `==x==`, and `^^x^^` markers (strikethrou...
High-risk advisory
CVE-2026-59922
Summary
Mistune plugins/formatting: quadratic-time parsing on long runs of `~~x~~`, `==x==`, and `^^x^^` markers (strikethrough / mark / insert)
Why it matters
GitHub has published a reviewed security advisory for mistune. Prioritize it with other application dependency updates, especially because EPSS places it in the 29% percentile.
Operator check
Check whether mistune is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. EPSS probability: 0.4%; percentile: 29%.
Sources
PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.