CVE-2026-42009

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-05-18. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — Patch released this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: None knownExposed: 0

A fix is available — apply it.

A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: 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%
Exploitation1% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
70%
KEV
Not listed

Published

May 18, 2026

Last Modified

September 18, 2026

Advisory Details (2)

Auto-updated May 18, 2026
Patch available. Sources: redhat.
redhat

2467279 – (CVE-2026-42009) CVE-2026-42009 gnutls: gnutls: Denial of Service via DTLS packet reordering vulnerability

https://bugzilla.redhat.com/show_bug.cgi?id=2467279
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-42009

Vendor Advisories for CVE-2026-42009(20)

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

Patch Availability(30)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulibgnutlsxx28 (3.4.10-4ubuntu1.9+esm3) @ xenial2026-09-18ubuntu
redhatrhcos-413.92.202609080414-02026-09-17redhat
redhatrhcos-412.86.202608241157-02026-09-03redhat
redhatrhcos-417.94.202608250221-02026-09-03redhat
redhatrhcos-416.94.202608150307-02026-08-31redhat
redhatrhcos-415.92.202608180329-02026-08-31redhat
redhatrhcos-414.92.202608172040-02026-08-31redhat
redhatrhcos-418.94.202608142238-02026-08-26redhat
redhatrhui5/rhua-tp-rhel9:17872412602026-08-24redhat
redhatrhcos-4.19.9.6.202607151909-02026-07-22redhat
redhatgnutls-0:3.7.6-21.el9_2.72026-07-20redhat
redhatrhcos-4.20.9.6.202607010620-02026-07-07redhat
redhatrhcos-4.21.9.6.202607011303-02026-07-07redhat
redhatrhaiis/model-opt-cuda-rhel9:17829510512026-07-06redhat
redhatrhaiis/vllm-rocm-rhel9:17829512442026-07-06redhat
redhatrhaiis/vllm-cuda-rhel9:17829510122026-07-06redhat
redhatgnutls-0:3.3.29-9.el7_9.12026-07-01redhat
redhatrhcos-4.22.9.8.202606230855-02026-06-30redhat
redhatlibtasn1-0:4.13-3.el8_4.12026-06-29redhat
redhatgnutls-0:3.8.3-4.el9_4.62026-06-29redhat
redhatlibtasn1-0:4.13-3.el8_6.22026-06-29redhat
redhatlibtasn1-0:4.13-4.el8_8.12026-06-29redhat
redhatgnutls-0:3.8.3-6.el9_6.42026-06-25redhat
redhatdiscovery/discovery-ui-rhel9:17821669522026-06-24redhat
redhatrhui5/rhua-rhel9:17815257392026-06-16redhat
redhatgnutls-0:3.8.9-9.el10_0.192026-06-16redhat
redhatgnutls-0:3.8.10-4.el9_82026-05-26redhat
redhatgnutls-0:3.6.16-8.el8_10.62026-05-26redhat
redhatgnutls-0:3.8.10-4.el10_22026-05-26redhat
redhatgnutls-main-3.8.13-1.hum12026-05-02redhat

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

(9 across 9 ecosystems)
Alpine:v3.20(1)
PackageVulnerable rangeFixed inDependents
gnutls—3.8.13-r0—
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
gnutls—3.8.13-r0—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
gnutls—3.8.13-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
gnutls—3.8.13-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
gnutls—3.8.13-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
gnutls283.7.1-5 ... 3.7.1-5+deb11u9 (10 versions)3.7.1-5+deb11u10—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
gnutls283.7.9-2 ... 3.7.9-2+deb12u6 (7 versions)3.7.9-2+deb12u7—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
gnutls283.8.9-3, 3.8.9-3+deb13u1, 3.8.9-3+deb13u2, 3.8.9-3+deb13u33.8.9-3+deb13u4—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
gnutls283.8.10-1 ... 3.8.9-3 (11 versions)3.8.13-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(10)

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 18× in last 7d / 144× 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 413 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-42009?
CVE-2026-42009 is a high vulnerability published on May 18, 2026. A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This…
When was CVE-2026-42009 disclosed?
CVE-2026-42009 was first published in the National Vulnerability Database on May 18, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42009 actively exploited?
CVE-2026-42009 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 30.1% of all scored CVEs.
What is the CVSS score of CVE-2026-42009?
CVE-2026-42009 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-42009?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42009, 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-2026-42009

Explore →

Is Your Infrastructure Affected by CVE-2026-42009?

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

Start Free Scan →Browse All CVEs