CVE-2026-33079

HIGHCVSS 7.58.7▲
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.7 under NVD CVSS v3. EPSS exploit probability: 0.0%, top 94% of all CVEs by exploit prediction. 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, nvd
Elevated
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

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

In versions 3.0.0a1 through 3.2.0 of Mistune, there is a ReDoS (Regular Expression Denial of Service) vulnerability in LINK_TITLE_RE that allows an attacker who can supply Markdown for parsing to cause denial of service. The regular expression used for parsing link titles contains overlapping alternatives that can trigger catastrophic backtracking. In both the double-quoted and single-quoted branches, a backslash followed by punctuation can be matched either as an escaped punctuation sequence or as two ordinary characters, creating an ambiguous pattern inside a repeated group. If an attacker supplies Markdown containing repeated ! sequences with no closing quote, the regex engine explores an exponential number of backtracking paths. This is reachable through normal Markdown parsing of inline links and block link reference definitions. A small crafted input can therefore cause significant CPU consumption and make applications using Mistune unresponsive.

CVSS v3
7.5
EG Score
8.7(medium)
EPSS
38.1%
KEV
Not listed

Published

May 6, 2026

Last Modified

July 8, 2026

Advisory Details (2)

Auto-updated May 6, 2026
🔬 Proof of concept available. Patch available. Sources: github.
github Patch Available🟡 PoC Available

ReDoS in LINK_TITLE_RE allows denial of service via crafted Markdown input · Advisory · lepture/mistune · GitHub

https://github.com/lepture/mistune/security/advisories/GHSA-8mp2-v27r-99xp
generic

mistune/src/mistune/helpers.py at df23edd60b43b639d2e6760ef9dd3d618aa11c21 · lepture/mistune · GitHub

https://github.com/lepture/mistune/blob/df23edd60b43b639d2e6760ef9dd3d618aa11c21/src/mistune/helpers.py#L20-L25

Vendor Advisories for CVE-2026-33079(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
mistune3.0.0 ... 3.2.0 (17 versions)3.2.1—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 46× 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 129 total refreshes for this CVE.

  1. 2026-07-11 08:27 UTCEPSS rescore
  2. 2026-07-09 19:10 UTCEPSS rescore
  3. 2026-07-08 15:15 UTCEPSS rescore
  4. 2026-07-07 13:46 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-06-30 23:22 UTCEPSS rescore
  11. 2026-06-30 04:33 UTCNVD updateCVSS v3 → 7.5
  12. 2026-06-29 14:06 UTCEPSS rescore
  13. 2026-06-29 14:06 UTCEPSS rescore
  14. 2026-06-28 14:07 UTCEPSS rescore
  15. 2026-06-28 14:07 UTCEPSS rescore
  16. 2026-06-28 04:56 UTCEPSS rescore
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-27 03:08 UTCEPSS rescore
  19. 2026-06-25 13:49 UTCEPSS rescore
  20. 2026-06-25 13:49 UTCEPSS rescore
  21. 2026-06-24 14:05 UTCEPSS rescore
  22. 2026-06-23 21:33 UTCEPSS rescore
  23. 2026-06-23 21:33 UTCEPSS rescore
  24. 2026-06-22 14:25 UTCEPSS rescore
  25. 2026-06-22 14:25 UTCEPSS rescore
Show 75 more
  1. 2026-06-21 14:56 UTCEPSS rescore
  2. 2026-06-21 14:56 UTCEPSS rescore
  3. 2026-06-21 01:59 UTCEPSS rescore
  4. 2026-06-19 19:25 UTCEPSS rescore
  5. 2026-06-19 19:25 UTCEPSS rescore
  6. 2026-06-18 17:52 UTCEPSS rescore
  7. 2026-06-18 17:52 UTCEPSS rescore
  8. 2026-06-17 17:53 UTCEPSS rescore
  9. 2026-06-16 17:52 UTCEPSS rescore
  10. 2026-06-15 17:49 UTCEPSS rescore
  11. 2026-06-14 23:18 UTCEPSS rescore
  12. 2026-06-14 19:50 UTCEG score recompute
  13. 2026-06-14 19:50 UTCVendor advisory
  14. 2026-06-14 07:26 UTCEG score recompute
  15. 2026-06-14 07:26 UTCVendor advisory
  16. 2026-06-13 23:00 UTCEPSS rescore
  17. 2026-06-12 23:44 UTCEG score recompute
  18. 2026-06-12 23:44 UTCVendor advisory
  19. 2026-06-12 23:12 UTCEPSS rescore
  20. 2026-06-12 23:12 UTCEPSS rescore
  21. 2026-06-12 02:24 UTCEG score recompute
  22. 2026-06-11 14:02 UTCEG score recompute
  23. 2026-06-11 14:02 UTCVendor advisory
  24. 2026-06-11 01:40 UTCEG score recompute
  25. 2026-06-11 01:40 UTCVendor advisory
  26. 2026-06-10 22:18 UTCEPSS rescore
  27. 2026-06-10 13:22 UTCEPSS rescore
  28. 2026-06-10 11:21 UTCEG score recompute
  29. 2026-06-10 11:21 UTCVendor advisory
  30. 2026-06-09 22:59 UTCEG score recompute
  31. 2026-06-09 22:59 UTCVendor advisory
  32. 2026-06-09 10:35 UTCEG score recompute
  33. 2026-06-09 10:35 UTCVendor advisory
  34. 2026-06-08 22:11 UTCEG score recompute
  35. 2026-06-08 22:11 UTCVendor advisory
  36. 2026-06-08 14:17 UTCEPSS rescore
  37. 2026-06-08 14:17 UTCEPSS rescore
  38. 2026-06-08 03:34 UTCEG score recompute
  39. 2026-06-08 03:34 UTCVendor advisory
  40. 2026-06-07 15:25 UTCEPSS rescore
  41. 2026-06-07 15:25 UTCEPSS rescore
  42. 2026-06-07 15:25 UTCEPSS rescore
  43. 2026-06-07 15:13 UTCEG score recompute
  44. 2026-06-07 15:13 UTCVendor advisory
  45. 2026-06-07 02:51 UTCEG score recompute
  46. 2026-06-07 02:51 UTCVendor advisory
  47. 2026-06-06 14:29 UTCEG score recompute
  48. 2026-06-06 14:29 UTCVendor advisory
  49. 2026-06-06 13:47 UTCEPSS rescore
  50. 2026-06-06 13:47 UTCEPSS rescore
  51. 2026-06-06 02:05 UTCEG score recompute
  52. 2026-06-06 02:05 UTCVendor advisory
  53. 2026-06-05 22:47 UTCEPSS rescore
  54. 2026-06-05 22:47 UTCEPSS rescore
  55. 2026-06-05 13:24 UTCEG score recompute
  56. 2026-06-05 13:24 UTCVendor advisory
  57. 2026-06-05 06:10 UTCEPSS rescore
  58. 2026-06-05 06:10 UTCEPSS rescore
  59. 2026-06-05 01:02 UTCEG score recompute
  60. 2026-06-05 01:02 UTCVendor advisory
  61. 2026-06-04 13:12 UTCEPSS rescore
  62. 2026-06-04 13:12 UTCEPSS rescore
  63. 2026-06-04 11:38 UTCEG score recompute
  64. 2026-06-04 11:38 UTCVendor advisory
  65. 2026-06-03 23:16 UTCEG score recompute
  66. 2026-06-03 23:16 UTCVendor advisory
  67. 2026-06-03 10:54 UTCEG score recompute
  68. 2026-06-03 10:54 UTCVendor advisory
  69. 2026-06-02 22:32 UTCEG score recompute
  70. 2026-06-02 22:32 UTCVendor advisory
  71. 2026-06-02 20:13 UTCEPSS rescore
  72. 2026-06-02 10:10 UTCEG score recompute
  73. 2026-06-02 10:10 UTCVendor advisory
  74. 2026-06-01 21:48 UTCEG score recompute
  75. 2026-06-01 21:48 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-33079?
CVE-2026-33079 is a high vulnerability published on May 6, 2026. In versions 3.0.0a1 through 3.2.0 of Mistune, there is a ReDoS (Regular Expression Denial of Service) vulnerability in LINKTITLERE that allows an attacker who can supply Markdown for parsing to cause denial of service. The regular expression used for parsing link titles contains overlapping…
When was CVE-2026-33079 disclosed?
CVE-2026-33079 was first published in the National Vulnerability Database on May 6, 2026, with the most recent update on July 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33079 actively exploited?
CVE-2026-33079 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 38.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-33079?
CVE-2026-33079 has a CVSS v3 base score of 7.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.7.
How do I remediate CVE-2026-33079?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33079, 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

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