CVE-2026-1117587.5HighCWE-407

CVE-2026-111758: markdown-it: Quadratic-time rendering of a single multi-line link reference definition with default options (regression since 14.0)

markdown-it

Affected: markdown-it · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.6%probability of exploitation in the next 30 days

46th percentile

050100

Higher than 46% of scored CVEs

7.5HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

markdown-it is a Markdown parser. From versions 14.1.0 to before 14.3.3, and 15.0.0 to before 15.0.3, a link reference definition whose label or title is never closed is O(n²) with default options. Continuation lines are pulled lazily with str += lineContent in src/rules_block/reference.ts, and the subsequent charCodeAt and slice calls flatten the V8 cons-string, copying everything collected so far; this runs before the rule decides the definition is invalid. No options are required to trigger it. This issue has been patched in versions 14.3.3 and 15.0.3.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

markdown-it · markdown-it>= 14.1.0, < 14.3.3; >= 15.0.0, < 15.0.3

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Inefficient Algorithmic Complexity · Denial of Service
Vendor: markdown-it
Published: October 2026
Band: Unlikely (under 1%), October 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-111758 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.