CVE-2026-50159

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.6% (46th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.6%CVSS: 5.3Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.8 and 11.16.1, Mermaid is vulnerable to CSS injection via sibling combinator selectors generated from diagram-supplied class or id names. An attacker who can supply diagram text can inject arbitrary CSS into the rendered page, potentially altering the appearance or behavior of unrelated page elements. This issue is fixed in versions 10.9.8 and 11.16.1.

CVSS v3
5.3
EG Score
5.3MEDIUMmedium confidence
EG Risk
24
EG Risk 24/100CISA SSVC

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
Severity53% × 45%
Exploitation1% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.6%
EPSS %ILE
46th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 6, 2026

Last Modified

September 8, 2026

Advisory Details (6)

Auto-updated Aug 6, 2026
Patch available. Sources: github, github_commit, github_pr, github_release.
github Patch Available

Mermaid allows CSS injection applying to sibling elements of the diagram · Advisory · mermaid-js/mermaid · GitHub

https://github.com/mermaid-js/mermaid/security/advisories/GHSA-6x64-9x62-f2gx
github_release Patch Available

v10.9.8

Patch available: mermaid-js/mermaid v10.9.8

https://github.com/mermaid-js/mermaid/releases/tag/v10.9.8
github_release Patch Available

[email protected]

Patch available: mermaid-js/mermaid [email protected]

https://github.com/mermaid-js/mermaid/releases/tag/[email protected]
github_pr Patch Available

Release Candidate 11.16.1

Patch available: mermaid-js/mermaid [email protected] (PR #8022 merged 2026-08-04)

https://github.com/mermaid-js/mermaid/pull/8022
github_commit Patch Available

commit 7e83f1533318 (mermaid-js/mermaid)

Patch available: mermaid-js/mermaid v10.9.8 (contains commit 7e83f1533318)

https://github.com/mermaid-js/mermaid/commit/7e83f1533318b307764d961906a73377266f4c5e
github_commit Patch Available

commit 12d472c9ed43 (mermaid-js/mermaid)

Patch available: mermaid-js/mermaid [email protected] (contains commit 12d472c9ed43)

https://github.com/mermaid-js/mermaid/commit/12d472c9ed43f94814b110da8d7a9ae6dd5266ed

Vendor Advisories for CVE-2026-50159(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
node-mermaid8.11.0+ds+~cs29.13.22-1 ... 9.2.2+~2.0.0-2 (15 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
node-mermaid8.11.0+ds+~cs29.13.22-1 ... 9.2.2+~2.0.0-2 (16 versions)
  • every version on: no fix on record
—
npm(1)
PackageVulnerable rangeFix by version rangeDependents
mermaid—
  • 11.0.0-alpha.1 up to 11.16.1: fixed in 11.16.1
  • every version up to 10.9.8: fixed in 10.9.8
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 44× 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. 2026-10-05 08:22 UTCEG score recompute
  2. 2026-10-04 23:22 UTCEPSS rescore
  3. 2026-10-04 05:48 UTCEG score recompute
  4. 2026-10-03 14:26 UTCEPSS rescore
  5. 2026-10-02 17:56 UTCEPSS rescore
  6. 2026-10-02 09:38 UTCEG score recompute
  7. 2026-10-01 19:50 UTCEPSS rescore
  8. 2026-09-30 23:00 UTCEG score recompute
  9. 2026-09-30 15:03 UTCEPSS rescore
  10. 2026-09-29 05:52 UTCEG score recompute
  11. 2026-09-28 13:51 UTCEPSS rescore
  12. 2026-09-27 17:28 UTCEG score recompute
  13. 2026-09-27 13:48 UTCEPSS rescore
  14. 2026-09-26 15:59 UTCEPSS rescore
  15. 2026-09-26 00:27 UTCEPSS rescore
  16. 2026-09-25 04:21 UTCEG score recompute
  17. 2026-09-23 21:17 UTCEG score recompute
  18. 2026-09-23 17:53 UTCEPSS rescore
  19. 2026-09-22 22:50 UTCEG score recompute
  20. 2026-09-22 01:01 UTCEG score recompute
  21. 2026-09-20 20:35 UTCEG score recompute
  22. 2026-09-20 20:16 UTCEPSS rescore
  23. 2026-09-19 21:26 UTCEG score recompute
  24. 2026-09-18 23:28 UTCEG score recompute
  25. 2026-09-18 19:28 UTCEPSS rescore
Show 72 more
  1. 2026-09-18 01:40 UTCEG score recompute
  2. 2026-09-17 03:51 UTCEG score recompute
  3. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-15 07:03 UTCEG score recompute
  6. 2026-09-14 09:14 UTCEG score recompute
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-13 11:25 UTCEG score recompute
  9. 2026-09-11 15:47 UTCEG score recompute
  10. 2026-09-11 14:53 UTCEPSS rescore
  11. 2026-09-10 17:44 UTCEG score recompute
  12. 2026-09-10 09:35 UTCEPSS rescore
  13. 2026-09-09 19:10 UTCEG score recompute
  14. 2026-09-08 22:01 UTCEPSS rescore
  15. 2026-09-07 21:11 UTCEG score recompute
  16. 2026-09-07 16:01 UTCEPSS rescore
  17. 2026-09-06 23:21 UTCEG score recompute
  18. 2026-09-06 13:47 UTCEPSS rescore
  19. 2026-09-06 01:29 UTCEG score recompute
  20. 2026-09-05 03:29 UTCEG score recompute
  21. 2026-09-04 05:06 UTCEPSS rescore
  22. 2026-09-03 06:12 UTCEG score recompute
  23. 2026-09-02 14:12 UTCEPSS rescore
  24. 2026-09-02 06:56 UTCEG score recompute
  25. 2026-09-01 13:54 UTCEPSS rescore
  26. 2026-09-01 07:11 UTCEG score recompute
  27. 2026-09-01 04:40 UTCEPSS rescore
  28. 2026-08-31 06:37 UTCEG score recompute
  29. 2026-08-30 19:17 UTCEPSS rescore
  30. 2026-08-30 08:25 UTCEG score recompute
  31. 2026-08-30 01:22 UTCEPSS rescore
  32. 2026-08-29 10:36 UTCEG score recompute
  33. 2026-08-28 21:41 UTCEPSS rescore
  34. 2026-08-27 20:50 UTCEG score recompute
  35. 2026-08-27 14:25 UTCEPSS rescore
  36. 2026-08-26 23:01 UTCEG score recompute
  37. 2026-08-26 14:46 UTCEPSS rescore
  38. 2026-08-26 01:11 UTCEG score recompute
  39. 2026-08-25 13:49 UTCEPSS rescore
  40. 2026-08-25 03:22 UTCEG score recompute
  41. 2026-08-23 07:44 UTCEG score recompute
  42. 2026-08-23 00:19 UTCEPSS rescore
  43. 2026-08-22 09:56 UTCEG score recompute
  44. 2026-08-21 23:49 UTCEPSS rescore
  45. 2026-08-21 12:07 UTCEG score recompute
  46. 2026-08-20 22:55 UTCEPSS rescore
  47. 2026-08-20 14:18 UTCEG score recompute
  48. 2026-08-19 17:04 UTCEPSS rescore
  49. 2026-08-18 17:53 UTCEG score recompute
  50. 2026-08-18 13:48 UTCEPSS rescore
  51. 2026-08-17 19:24 UTCEG score recompute
  52. 2026-08-17 13:47 UTCEPSS rescore
  53. 2026-08-16 20:36 UTCEG score recompute
  54. 2026-08-16 14:56 UTCEPSS rescore
  55. 2026-08-16 02:14 UTCEPSS rescore
  56. 2026-08-15 22:47 UTCEG score recompute
  57. 2026-08-15 01:30 UTCEPSS rescore
  58. 2026-08-14 03:09 UTCEG score recompute
  59. 2026-08-13 22:00 UTCEPSS rescore
  60. 2026-08-13 05:20 UTCEG score recompute
  61. 2026-08-12 13:51 UTCEPSS rescore
  62. 2026-08-12 07:31 UTCEG score recompute
  63. 2026-08-11 09:42 UTCEG score recompute
  64. 2026-08-11 00:00 UTCEPSS rescore
  65. 2026-08-09 14:04 UTCEG score recompute
  66. 2026-08-09 13:46 UTCEPSS rescore
  67. 2026-08-08 16:37 UTCEPSS rescore
  68. 2026-08-07 18:27 UTCEG score recompute
  69. 2026-08-07 17:27 UTCEG score recompute
  70. 2026-08-06 22:19 UTCEG score recompute▲ 5.30
  71. 2026-08-06 22:18 UTCNVD updateCVSS v3 → 5.3 · CVSS v4 → 5.3
  72. 2026-08-06 20:07 UTCEG score recompute

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-50159?
CVE-2026-50159 is a medium vulnerability published on August 6, 2026. Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.8 and 11.16.1, Mermaid is vulnerable to CSS injection via sibling combinator selectors generated from diagram-supplied class or id names. An attacker who can supply diagram text can…
When was CVE-2026-50159 disclosed?
CVE-2026-50159 was first published on August 6, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-50159 actively exploited?
CVE-2026-50159 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.6% probability of exploitation in the next 30 days (46th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-50159?
CVE-2026-50159 has a CVSS base score of 5.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-50159?
A fix for CVE-2026-50159 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-50159 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-50159

Explore →

Is Your Infrastructure Affected by CVE-2026-50159?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs