CVE-2026-59929

MEDIUMPre-NVD 6.16.1—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (25th 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
6.1EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 6.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:, and res: to reach rendered href and src attributes and potentially execute script in affected user agents. This issue is fixed in version 3.3.0.

CVSS v3
6.1
EG Score
6.1MEDIUMmedium confidence
EG Risk
28
EG Risk 28/100CISA 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
Severity61% × 45%
Exploitation0% × 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
0.3%
EPSS %ILE
25th
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

July 8, 2026

Last Modified

July 9, 2026

Advisory Details (3)

Auto-updated Jul 8, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
githubMentions a patch (unverified)🟡 PoC Available

renderers/html.safe_url: HARMFUL_PROTOCOLS list misses legacy and chained schemes (`feed:`, `view-source:`, `jar:`, `livescript:`, `mocha:`, `ms-its:`, `mk:`, `res:`, `data:`-aliases) that historically chain to `javascript:` execution · Advisory · lepture/mistune · GitHub

https://github.com/lepture/mistune/security/advisories/GHSA-qfrw-5rxm-mhh2
github_release Patch Available

v3.3.0

Patch available: lepture/mistune v3.3.0

https://github.com/lepture/mistune/releases/tag/v3.3.0
github_commit Patch Available

commit c7101fcbb6e8 (lepture/mistune)

Patch available: lepture/mistune v3.3.0 (contains commit c7101fcbb6e8)

https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc

Vendor Advisories for CVE-2026-59929(1)

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

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
mistune0.8.4-4 ... 3.1.4-1 (15 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
mistune2.0.4-1 ... 3.3.4-1 (7 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
mistune3.1.3-1, 3.1.4-1, 3.3.4-1
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
mistune3.1.3-1, 3.1.4-1, 3.3.4-1
  • every version on: no fix on record
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
mistune0.1.0 ... 3.2.1 (51 versions)
  • every version up to 3.3.0: fixed in 3.3.0
—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 32× 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.

Showing the most recent 100 of 137 total refreshes for this CVE.

  1. 2026-10-09 20:07 UTCEPSS rescore
  2. 2026-10-08 17:13 UTCEPSS rescore
  3. 2026-10-07 23:48 UTCEPSS rescore
  4. 2026-10-06 15:18 UTCEPSS rescore
  5. 2026-10-05 17:43 UTCEPSS rescore
  6. 2026-10-04 23:22 UTCEPSS rescore
  7. 2026-10-03 14:26 UTCEPSS rescore
  8. 2026-10-02 17:56 UTCEPSS rescore
  9. 2026-10-01 19:50 UTCEPSS rescore
  10. 2026-10-01 16:11 UTCEG score recompute
  11. 2026-09-30 15:03 UTCEPSS rescore
  12. 2026-09-29 15:22 UTCEPSS rescore
  13. 2026-09-28 13:51 UTCEPSS rescore
  14. 2026-09-28 13:22 UTCEG score recompute
  15. 2026-09-27 13:48 UTCEPSS rescore
  16. 2026-09-26 15:59 UTCEPSS rescore
  17. 2026-09-24 14:04 UTCEPSS rescore
  18. 2026-09-24 11:48 UTCEG score recompute
  19. 2026-09-23 17:54 UTCEPSS rescore
  20. 2026-09-23 06:10 UTCEG score recompute
  21. 2026-09-20 20:16 UTCEPSS rescore
  22. 2026-09-18 19:28 UTCEPSS rescore
  23. 2026-09-18 05:43 UTCEG score recompute
  24. 2026-09-17 19:31 UTCEPSS rescore
  25. 2026-09-16 14:08 UTCEPSS rescore
Show 75 more
  1. 2026-09-16 05:15 UTCEPSS rescore
  2. 2026-09-15 03:11 UTCEPSS rescore
  3. 2026-09-14 07:59 UTCEG score recompute
  4. 2026-09-13 16:47 UTCEPSS rescore
  5. 2026-09-13 08:24 UTCEG score recompute
  6. 2026-09-12 03:34 UTCEG score recompute
  7. 2026-09-11 14:53 UTCEPSS rescore
  8. 2026-09-10 09:35 UTCEPSS rescore
  9. 2026-09-08 22:01 UTCEPSS rescore
  10. 2026-09-07 16:01 UTCEPSS rescore
  11. 2026-09-06 13:47 UTCEPSS rescore
  12. 2026-09-05 22:48 UTCEG score recompute
  13. 2026-09-04 05:07 UTCEPSS rescore
  14. 2026-09-02 14:12 UTCEPSS rescore
  15. 2026-09-01 13:54 UTCEPSS rescore
  16. 2026-09-01 04:40 UTCEPSS rescore
  17. 2026-08-30 19:17 UTCEPSS rescore
  18. 2026-08-30 07:30 UTCEG score recompute
  19. 2026-08-30 01:22 UTCEPSS rescore
  20. 2026-08-28 21:42 UTCEPSS rescore
  21. 2026-08-27 21:50 UTCEG score recompute
  22. 2026-08-27 14:25 UTCEPSS rescore
  23. 2026-08-26 14:46 UTCEPSS rescore
  24. 2026-08-26 08:23 UTCEG score recompute
  25. 2026-08-25 13:49 UTCEPSS rescore
  26. 2026-08-25 03:34 UTCEG score recompute
  27. 2026-08-23 03:20 UTCEG score recompute
  28. 2026-08-23 00:19 UTCEPSS rescore
  29. 2026-08-22 03:47 UTCEG score recompute
  30. 2026-08-21 23:49 UTCEPSS rescore
  31. 2026-08-21 03:59 UTCEG score recompute
  32. 2026-08-20 22:55 UTCEPSS rescore
  33. 2026-08-20 03:39 UTCEG score recompute
  34. 2026-08-19 17:04 UTCEPSS rescore
  35. 2026-08-19 03:57 UTCEG score recompute
  36. 2026-08-18 13:48 UTCEPSS rescore
  37. 2026-08-18 04:24 UTCEG score recompute
  38. 2026-08-17 13:47 UTCEPSS rescore
  39. 2026-08-17 04:40 UTCEG score recompute
  40. 2026-08-16 14:56 UTCEPSS rescore
  41. 2026-08-16 05:07 UTCEG score recompute
  42. 2026-08-16 02:14 UTCEPSS rescore
  43. 2026-08-15 05:34 UTCEG score recompute
  44. 2026-08-15 01:30 UTCEPSS rescore
  45. 2026-08-14 06:01 UTCEG score recompute
  46. 2026-08-13 22:00 UTCEPSS rescore
  47. 2026-08-13 06:28 UTCEG score recompute
  48. 2026-08-12 13:51 UTCEPSS rescore
  49. 2026-08-12 06:55 UTCEG score recompute
  50. 2026-08-11 07:22 UTCEG score recompute
  51. 2026-08-11 00:00 UTCEPSS rescore
  52. 2026-08-10 07:49 UTCEG score recompute
  53. 2026-08-09 13:46 UTCEPSS rescore
  54. 2026-08-09 08:17 UTCEG score recompute
  55. 2026-08-08 16:37 UTCEPSS rescore
  56. 2026-08-08 08:44 UTCEG score recompute
  57. 2026-08-07 09:11 UTCEG score recompute
  58. 2026-08-06 13:47 UTCEPSS rescore
  59. 2026-08-06 09:39 UTCEG score recompute
  60. 2026-08-05 19:17 UTCEPSS rescore
  61. 2026-08-05 10:06 UTCEG score recompute
  62. 2026-08-04 15:10 UTCEPSS rescore
  63. 2026-08-04 10:39 UTCEPSS rescore
  64. 2026-08-04 10:12 UTCEG score recompute
  65. 2026-08-03 10:36 UTCEPSS rescore
  66. 2026-08-02 10:16 UTCEG score recompute
  67. 2026-08-02 02:27 UTCEPSS rescore
  68. 2026-08-01 10:42 UTCEG score recompute
  69. 2026-08-01 04:16 UTCEPSS rescore
  70. 2026-07-31 11:09 UTCEG score recompute
  71. 2026-07-30 16:28 UTCEPSS rescore
  72. 2026-07-30 11:32 UTCEG score recompute
  73. 2026-07-30 01:30 UTCEPSS rescore
  74. 2026-07-30 01:30 UTCEPSS rescore
  75. 2026-07-29 11:56 UTCEG score recompute

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-59929?
CVE-2026-59929 is a medium vulnerability published on July 8, 2026. Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the safe_url filter in src/mistune/renderers/html.py blocks only javascript:, vbscript:, file:, and data: schemes, allowing legacy or chained schemes such as feed:, view-source:, jar:, livescript:, mocha:, ms-its:, mk:,…
When was CVE-2026-59929 disclosed?
CVE-2026-59929 was first published on July 8, 2026, with the most recent update on July 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-59929 actively exploited?
CVE-2026-59929 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-59929?
CVE-2026-59929 has a CVSS base score of 6.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-59929?
A fix for CVE-2026-59929 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-59929 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-2026-59929

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