CVE-2026-3276

MEDIUMPre-NVD 6.36.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 60% 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, secondary
Trending — 5 sources updated this week
6.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.3Exploit: None knownExposed: 0

A fix is available — apply it.

unicodedata.normalize() can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms.

CVSS v3
6.3
EG Score
6.3(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: 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
Severity63% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
41%
KEV
Not listed

Published

June 3, 2026

Last Modified

August 13, 2026

Advisory Details (8)

Auto-updated Jun 13, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit, github_pr.
generic

oss-security - [CVE-2026-3276] Potential DoS via quadratic complexity in unicodedata.normalize()

http://www.openwall.com/lists/oss-security/2026/06/03/15
generic

Mailman 3 [CVE-2026-3276] Potential DoS via quadratic complexity in unicodedata.normalize() - Security-announce - python.org

https://mail.python.org/archives/list/[email protected]/thread/PP5HB4K7727OBBM76KA2ILID76K3OZGZ/
github_pr

gh-149079: Fix O(n^2) canonical ordering in unicodedata.normalize()

Fix merged in python/cpython PR #149080 on 2026-06-02 — awaiting tagged release

https://github.com/python/cpython/pull/149080
generic

Issue · GitHub

https://github.com/python/cpython/issues/149079
github_commit

commit c5512bd7c1dc (python/cpython)

Fix landed in python/cpython commit c5512bd7c1dc — awaiting tagged release

https://github.com/python/cpython/commit/c5512bd7c1dc28055660565275012766941d3066
github_commit

commit ba785b88add9 (python/cpython)

Fix landed in python/cpython commit ba785b88add9 — awaiting tagged release

https://github.com/python/cpython/commit/ba785b88add96acbf403d65cb157fb2743a33a32
github_commit

commit 991224b1e831 (python/cpython)

Fix landed in python/cpython commit 991224b1e831 — awaiting tagged release

https://github.com/python/cpython/commit/991224b1e8311c85f198f6dd8208bf8cff7fc26f
github_commit

commit 6b505d1f41f8 (python/cpython)

Fix landed in python/cpython commit 6b505d1f41f8 — awaiting tagged release

https://github.com/python/cpython/commit/6b505d1f41f8f3ea0fe5a4786d3a8fff1875cfc0

Vendor Advisories for CVE-2026-3276(2)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntupython3.14-venv (3.14.4-1ubuntu0.1) @ resolute2026-09-14ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(7 across 5 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
python2.72.7.18-10 ... 2.7.18-9 (10 versions)——
python3.93.9.10-1 ... 3.9.9-4 (29 versions)——
Debian:14(2)
PackageVulnerable rangeFixed inDependents
python3.133.13.11-1 ... 3.13.9-1 (7 versions)3.13.14-1—
python3.143.14.0-1 ... 3.14.5~rc1-1 (23 versions)3.14.6-1—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
python3—3.14.7-r0—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
python3.113.11.2-6 ... 3.11.9-1 (28 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
python3.133.13.5-2, 3.13.5-2+deb13u1, 3.13.5-2+deb13u23.13.5-2+deb13u3—

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 11× in last 7d / 42× 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 239 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-3276?
CVE-2026-3276 is a medium vulnerability published on June 3, 2026. unicodedata.normalize() can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms.
When was CVE-2026-3276 disclosed?
CVE-2026-3276 was first published in the National Vulnerability Database on June 3, 2026, with the most recent update on August 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-3276 actively exploited?
CVE-2026-3276 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 59.5% of all scored CVEs.
What is the CVSS score of CVE-2026-3276?
CVE-2026-3276 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2026-3276?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-3276, 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-2026-3276

Explore →

Is Your Infrastructure Affected by CVE-2026-3276?

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

Start Free Scan →Browse All CVEs