CVE-2026-8630

MEDIUMPre-NVD 6.16.1—
EchelonGraph scoreHIGH confidence

Score 6.1 from GitHub Security Advisory published 2026-08-23. a secondary CVSS source baseline 6.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
6.1EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

justhtml before 1.12.0 (versions <= 1.11.0) contains a mutation cross-site scripting (mXSS) vulnerability in the serialization of raw-text elements such as and . When a DOM tree is processed by sanitize_dom() using a custom policy that keeps these elements, text nodes inside them are serialized literally without escaping, allowing attacker-controlled text containing the matching closing tag sequence to break out of the raw-text context and inject arbitrary HTML into the serialized output. The default sanitization policy is not affected because it drops the contents of style and script.

CVSS v3
6.1
EG Score
6.1(high)
EG Risk
28(Track)
EG Risk 28/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity61% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
8%
KEV
Not listed

Published

August 23, 2026

Last Modified

August 26, 2026

Advisory Details (2)

Auto-updated Aug 23, 2026
Patch available. Sources: github.
generic

justhtml before 1.12.0 Mutation XSS via Raw Text Elements | Advisories | VulnCheck

https://www.vulncheck.com/advisories/justhtml-before-mutation-xss-via-raw-text-elements
github Patch Available

Mutation XSS via Literal Text Serialization in Raw Text Elements (style/script) · Advisory · EmilStenstrom/justhtml · GitHub

https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-qvc2-mg72-jjhx

Vendor Advisories for CVE-2026-8630(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
justhtml0.1.0 ... 1.9.1 (56 versions)1.12.0—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 16× in last 7d / 16× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-26 19:23 UTCEG score recompute
  2. 2026-08-26 19:23 UTCGHSA enrichment
  3. 2026-08-26 18:41 UTCEG score recompute
  4. 2026-08-26 18:41 UTCGHSA enrichment
  5. 2026-08-26 17:24 UTCEG score recompute
  6. 2026-08-26 17:24 UTCGHSA enrichment
  7. 2026-08-26 14:47 UTCEPSS rescore
  8. 2026-08-25 19:13 UTCEG score recompute
  9. 2026-08-25 19:13 UTCGHSA enrichment
  10. 2026-08-25 13:49 UTCEPSS rescore
  11. 2026-08-24 16:55 UTCEG score recompute
  12. 2026-08-24 16:55 UTCGHSA enrichment
  13. 2026-08-24 14:18 UTCEPSS rescore
  14. 2026-08-23 14:20 UTCEG score recompute
  15. 2026-08-23 13:51 UTCEG score recompute
  16. 2026-08-23 13:50 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-8630?
CVE-2026-8630 is a medium vulnerability published on August 23, 2026. justhtml before 1.12.0 (versions <= 1.11.0) contains a mutation cross-site scripting (mXSS) vulnerability in the serialization of raw-text elements such as <style> and <script>. When a DOM tree is processed by sanitize_dom() using a custom policy that keeps these elements, text nodes inside them…
When was CVE-2026-8630 disclosed?
CVE-2026-8630 was first published in the National Vulnerability Database on August 23, 2026, with the most recent update on August 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-8630 actively exploited?
CVE-2026-8630 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 91.6% of all scored CVEs.
What is the CVSS score of CVE-2026-8630?
CVE-2026-8630 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-8630?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8630, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-8630

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