CVE-2026-3644

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory published 2026-03-16. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
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

A fix is available — apply it.

The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation applied to BaseCookie.output().

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
34(Track)
EG Risk 34/100SSVC: 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
Severity75% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
34.3%
KEV
Not listed

Published

March 16, 2026

Last Modified

June 30, 2026

Advisory Details (6)

Auto-updated Jun 11, 2026
Upstream fix merged — awaiting tagged release. Sources: github_commit, github_pr.
generic

Mailman 3 [CVE-2026-3644] Incomplete control character validation in http.cookies - Security-announce - python.org

https://mail.python.org/archives/list/[email protected]/thread/H6CADMBCDRFGWCMOXWUIHFJNV43GABJ7/
github_pr

gh-145599: Reject control characters in `http.cookies.Morsel.update()` and `http.cookies.BaseCookie.js_output`

Fix merged in python/cpython PR #145600 on 2026-03-16 — awaiting tagged release

https://github.com/python/cpython/pull/145600
generic

Reject control characters in more places in `http.cookies.Morsel` · Issue #145599 · python/cpython · GitHub

https://github.com/python/cpython/issues/145599
github_commit

commit d16ecc6c3626 (python/cpython)

Fix landed in python/cpython commit d16ecc6c3626 — awaiting tagged release

https://github.com/python/cpython/commit/d16ecc6c3626f0e2cc8f08c309c83934e8a979dd
github_commit

commit 62ceb396fcbe (python/cpython)

Fix landed in python/cpython commit 62ceb396fcbe — awaiting tagged release

https://github.com/python/cpython/commit/62ceb396fcbe69da1ded3702de586f4072b590dd
github_commit

commit 57e88c1cf95e (python/cpython)

Fix landed in python/cpython commit 57e88c1cf95e — awaiting tagged release

https://github.com/python/cpython/commit/57e88c1cf95e1481b94ae57abe1010469d47a6b4

Vendor Advisories for CVE-2026-3644(12)

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

Patch Availability(10)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatrhui5/rhua-rhel9:17797982222026-05-27redhat
redhatpython3.12-0:3.12.13-2.el9_82026-05-19redhat
redhatpython3.14-0:3.14.4-2.el10_22026-05-19redhat
redhatpython3.12-0:3.12.13-2.el10_22026-05-19redhat
redhatpython3.14-0:3.14.4-2.el9_82026-05-19redhat
redhatpython3.12-0:3.12.13-2.el8_102026-04-27redhat
redhatpython3-11-main-3.11.15-4.hum12026-04-17redhat
redhatpython3-12-main-3.12.13-3.hum12026-04-17redhat
redhatpython3-14-main-3.14.4-1.hum12026-04-11redhat
redhatpython3-13-main-3.13.13-1.hum12026-04-10redhat

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.

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 37× 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. 2026-07-23 03:10 UTCEG score recompute
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-21 15:24 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-17 08:16 UTCOSV refresh
  9. 2026-07-16 17:03 UTCEPSS rescore
  10. 2026-07-15 16:57 UTCEPSS rescore
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 02:00 UTCEPSS rescore
  13. 2026-07-13 22:30 UTCEPSS rescore
  14. 2026-07-13 06:13 UTCEPSS rescore
  15. 2026-07-13 06:13 UTCEPSS rescore
  16. 2026-07-12 05:46 UTCEPSS rescore
  17. 2026-07-11 08:27 UTCEPSS rescore
  18. 2026-07-09 19:10 UTCEPSS rescore
  19. 2026-07-08 15:15 UTCEPSS rescore
  20. 2026-07-07 13:46 UTCEPSS rescore
  21. 2026-07-06 16:27 UTCEPSS rescore
  22. 2026-07-06 16:27 UTCEPSS rescore
  23. 2026-07-06 02:23 UTCEPSS rescore
  24. 2026-07-06 02:23 UTCEPSS rescore
  25. 2026-07-05 02:30 UTCEPSS rescore
Show 55 more
  1. 2026-07-04 06:31 UTCEPSS rescore
  2. 2026-07-01 15:06 UTCEPSS rescore
  3. 2026-06-30 23:22 UTCEPSS rescore
  4. 2026-06-29 14:06 UTCEPSS rescore
  5. 2026-06-29 06:02 UTCOSV refresh
  6. 2026-06-28 14:07 UTCEPSS rescore
  7. 2026-06-28 04:56 UTCEPSS rescore
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-25 13:49 UTCEPSS rescore
  10. 2026-06-25 13:49 UTCEPSS rescore
  11. 2026-06-24 14:05 UTCEPSS rescore
  12. 2026-06-23 21:33 UTCEPSS rescore
  13. 2026-06-22 14:25 UTCEPSS rescore
  14. 2026-06-22 14:25 UTCEPSS rescore
  15. 2026-06-21 14:56 UTCEPSS rescore
  16. 2026-06-21 14:56 UTCEPSS rescore
  17. 2026-06-21 01:59 UTCEPSS rescore
  18. 2026-06-19 19:25 UTCEPSS rescore
  19. 2026-06-18 17:52 UTCEPSS rescore
  20. 2026-06-18 17:52 UTCEPSS rescore
  21. 2026-06-17 17:53 UTCEPSS rescore
  22. 2026-06-16 17:52 UTCEPSS rescore
  23. 2026-06-15 17:49 UTCEPSS rescore
  24. 2026-06-13 23:00 UTCEPSS rescore
  25. 2026-06-12 23:12 UTCEPSS rescore
  26. 2026-06-12 23:12 UTCEPSS rescore
  27. 2026-06-11 23:55 UTCVendor advisory
  28. 2026-06-11 23:55 UTCGHSA enrichment
  29. 2026-06-11 14:00 UTCEPSS rescore
  30. 2026-06-10 22:18 UTCEPSS rescore
  31. 2026-06-10 18:56 UTCVendor advisory
  32. 2026-06-10 18:56 UTCGHSA enrichment
  33. 2026-06-10 13:22 UTCEPSS rescore
  34. 2026-06-10 05:51 UTCVendor advisory
  35. 2026-06-10 05:51 UTCGHSA enrichment
  36. 2026-06-09 16:40 UTCVendor advisory
  37. 2026-06-09 16:40 UTCGHSA enrichment
  38. 2026-06-08 14:17 UTCEPSS rescore
  39. 2026-06-08 14:17 UTCEPSS rescore
  40. 2026-06-08 03:36 UTCVendor advisory
  41. 2026-06-08 03:36 UTCGHSA enrichment
  42. 2026-06-07 15:25 UTCEPSS rescore
  43. 2026-06-07 15:25 UTCEPSS rescore
  44. 2026-06-07 15:25 UTCEPSS rescore
  45. 2026-06-07 14:31 UTCVendor advisory
  46. 2026-06-07 14:31 UTCGHSA enrichment
  47. 2026-06-06 13:47 UTCEPSS rescore
  48. 2026-06-06 13:47 UTCEPSS rescore
  49. 2026-06-05 22:47 UTCEPSS rescore
  50. 2026-06-05 22:47 UTCEPSS rescore
  51. 2026-06-05 06:10 UTCEPSS rescore
  52. 2026-06-05 06:10 UTCEPSS rescore
  53. 2026-06-04 21:14 UTCEG score recompute
  54. 2026-06-04 21:14 UTCVendor advisory
  55. 2026-06-04 21:14 UTCGHSA enrichment

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-3644?
CVE-2026-3644 is a high vulnerability published on March 16, 2026. The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update(), |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.js_output() lacked the output validation…
When was CVE-2026-3644 disclosed?
CVE-2026-3644 was first published in the National Vulnerability Database on March 16, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-3644 actively exploited?
CVE-2026-3644 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 34.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-3644?
CVE-2026-3644 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-3644?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-3644, 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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