What is CVE-2026-59710?
showdown contains a stored cross-site scripting vulnerability in the parseHeaders function of src/subParsers/makehtml/tables.js that fails to properly escape table header ID attributes. Attackers can inject arbitrary HTML and script-executing SVG elements through double-quote characters in markdown table headers, achieving stored XSS when untrusted markdown is rendered with the default github flavor configuration.
The record classifies CVE-2026-59710 under weakness class CWE-79. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 91 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 6.1 — MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS v4.0 base score
- 5.3
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 - EPSS (FIRST)
- 0.1% probability of exploitation in the next 30 days, higher than 9.7% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 5.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-06, last modified 2026-07-07
Is CVE-2026-59710 being exploited?
Weaponised exploit code for CVE-2026-59710 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 40 in the Threadlinqs vulnerability feed.
- trickest/cve (trickest)
Affected products and versions
- showdown: showdown
How to fix CVE-2026-59710
No vendor patch reference has been recorded for CVE-2026-59710 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-59710
No threat campaign in the Threadlinqs corpus currently references CVE-2026-59710, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.