CVE-2026-59925: inline_parser: quadratic-time parsing on long runs of `**x**` and `***x***` emphasis pairs
CSIRTS triage
- What
- This vulnerability causes quadratic-time parsing issues on long runs of emphasis pairs.
- Who is affected
- Users of Mistune are affected.
- Urgency
- Remediation is urgent due to the high severity of the vulnerability.
- Action
- Update to the latest version of Mistune to mitigate this issue.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch Mistune
Get an email when a new Mistune advisory drops — max one per day, one-click unsubscribe.
Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-59925
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-599250.36% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 28% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-59925 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
More from Microsoft Security Response Center
- highCVE-2026-12064: proto-default skips SSH verification2026-07-02
- unknownCVE-2026-14125: Chromium: CVE-2026-14125 Uninitialized Use in ANGLE2026-07-02
- mediumCVE-2026-57987: Microsoft Edge (Chromium-based) Spoofing Vulnerability2026-07-02
- unknownCVE-2026-13775: Chromium: CVE-2026-13775 Use after free in GPU2026-07-02
- unknownCVE-2026-13779: Chromium: CVE-2026-13779 Use after free in Chromoting2026-07-02