CVE-2026-28387

HIGHNVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-04-08. NVD baseline CVSS 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.1Exploit: None knownExposed: 0

A fix is available — apply it.

Issue summary: An uncommon configuration of clients performing DANE TLSA-based server authentication, when paired with uncommon server DANE TLSA records, may result in a use-after-free and/or double-free on the client side.

Impact summary: A use after free can have a range of potential consequences such as the corruption of valid data, crashes or execution of arbitrary code.

However, the issue only affects clients that make use of TLSA records with both the PKIX-TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate usage.

By far the most common deployment of DANE is in SMTP MTAs for which RFC7672 recommends that clients treat as 'unusable' any TLSA records that have the PKIX certificate usages. These SMTP (or other similar) clients are not vulnerable to this issue. Conversely, any clients that support only the PKIX usages, and ignore the DANE-TA(2) usage are also not vulnerable.

The client would also need to be communicating with a server that publishes a TLSA RRset with both types of TLSA records.

No FIPS modules are affected by this issue, the problem code is outside the FIPS module boundary.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
37(Track)
EG Risk 37/100SSVC: 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
Severity81% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
51%
KEV
Not listed

Published

April 7, 2026

Last Modified

July 24, 2026

Advisory Details (6)

Auto-updated May 10, 2026
No patch confirmed yet.
generic
https://openssl-library.org/news/secadv/20260407.txt
generic

dane_match_cert() should X509_free() on ->mcert instead · openssl/openssl@ec03fa0 · GitHub

https://github.com/openssl/openssl/commit/ec03fa050b3346997ed9c5fef3d0e16ad7db8177
generic

dane_match_cert() should X509_free() on ->mcert instead · openssl/openssl@7a4e08c · GitHub

https://github.com/openssl/openssl/commit/7a4e08cee62a728d32e60b0de89e6764339df0a7
generic

dane_match_cert() should X509_free() on ->mcert instead · openssl/openssl@444958d · GitHub

https://github.com/openssl/openssl/commit/444958deaf450aea819171f97ae69eaedede42c3
generic

dane_match_cert() should X509_free() on ->mcert instead · openssl/openssl@258a8f6 · GitHub

https://github.com/openssl/openssl/commit/258a8f63b26995ba357f4326da00e19e29c6acbe
generic

dane_match_cert() should X509_free() on ->mcert instead · openssl/openssl@07e727d · GitHub

https://github.com/openssl/openssl/commit/07e727d304746edb49a98ee8f6ab00256e1f012b

Vendor Advisories for CVE-2026-28387(2)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuopenssl1.0 (1.0.2n-1ubuntu5.13+esm4) @ bionic2026-07-26ubuntu
ubuntuopenssl-provider-legacy (3.5.3-1ubuntu3.3) @ questing2026-07-26ubuntu
redhatopenssl-main-3.5.6-0.1.hum12026-04-09redhat

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
openssl—3.3.7-r0—
Alpine:v3.21(1)
PackageVulnerable rangeFixed inDependents
openssl—3.3.7-r0—
Alpine:v3.22(1)
PackageVulnerable rangeFixed inDependents
openssl—3.5.6-r0—
Alpine:v3.23(1)
PackageVulnerable rangeFixed inDependents
openssl—3.5.6-r0—
Alpine:v3.24(1)
PackageVulnerable rangeFixed inDependents
openssl—3.5.6-r0—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
openssl1.1.1k-1 ... 1.1.1w-0~deb11u1 (22 versions)1.1.1w-0+deb11u7—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
openssl3.0.10-1 ... 3.0.9-1 (20 versions)3.0.19-1~deb12u2—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
openssl3.5.1-1 ... 3.5.5-1~deb13u1 (8 versions)3.5.5-1~deb13u2—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
openssl3.5.1-1 ... 3.6.1-3 (20 versions)3.6.2-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

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 6× in last 7d / 30× 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 237 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-28387?
CVE-2026-28387 is a high vulnerability published on April 7, 2026. Issue summary: An uncommon configuration of clients performing DANE TLSA-based server authentication, when paired with uncommon server DANE TLSA records, may result in a use-after-free and/or double-free on the client side. Impact summary: A use after free can have a range of potential consequences…
When was CVE-2026-28387 disclosed?
CVE-2026-28387 was first published in the National Vulnerability Database on April 7, 2026, with the most recent update on July 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-28387 actively exploited?
CVE-2026-28387 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 49.5% of all scored CVEs.
What is the CVSS score of CVE-2026-28387?
CVE-2026-28387 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-28387?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-28387, 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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