CVE-2026-28490

MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under NVD CVSS v3. EPSS exploit probability: 0.1%, top 96% 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
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: None knownExposed: 0

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

Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.9, a cryptographic padding oracle vulnerability was identified in the Authlib Python library concerning the implementation of the JSON Web Encryption (JWE) RSA1_5 key management algorithm. Authlib registers RSA1_5 in its default algorithm registry without requiring explicit opt-in, and actively destroys the constant-time Bleichenbacher mitigation that the underlying cryptography library implements correctly. This issue has been patched in version 1.6.9.

CVSS v3
6.5
EG Score
6.5(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
Severity65% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

March 16, 2026

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Aug 4, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
github Patch Available🟡 PoC Available

JWE RSA1_5 Bleichenbacher Padding Oracle · Advisory · authlib/authlib · GitHub

https://github.com/authlib/authlib/security/advisories/GHSA-7432-952r-cw78
github_release Patch Available

v1.6.9

Patch available: authlib/authlib v1.6.9

https://github.com/authlib/authlib/releases/tag/v1.6.9
github_commit Patch Available

commit 48b345f29f6c (authlib/authlib)

Patch available: authlib/authlib v1.6.9 (contains commit 48b345f29f6c)

https://github.com/authlib/authlib/commit/48b345f29f6c459f11c6a40162b6c0b742ef2e22

Affected Packages

(5 across 5 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
python-authlib0.15.4-1, 0.15.4-1+deb11u10.15.4-1+deb11u2—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
python-authlib1.2.0-1, 1.2.0-1+deb12u11.2.0-1+deb12u2—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
python-authlib1.6.0-1 ... 1.7.2-2 (13 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
python-authlib1.6.0-1 ... 1.6.8-1 (8 versions)1.6.9-1—
PyPI(1)
PackageVulnerable rangeFixed inDependents
authlib0.1 ... 1.6.8 (56 versions)1.6.9—

Weakness Classification(2)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

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

Frequently asked(5)

What is CVE-2026-28490?
CVE-2026-28490 is a medium vulnerability published on March 16, 2026. Authlib is a Python library which builds OAuth and OpenID Connect servers. Prior to version 1.6.9, a cryptographic padding oracle vulnerability was identified in the Authlib Python library concerning the implementation of the JSON Web Encryption (JWE) RSA15 key management algorithm. Authlib…
When was CVE-2026-28490 disclosed?
CVE-2026-28490 was first published in the National Vulnerability Database on March 16, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-28490 actively exploited?
CVE-2026-28490 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 96.2% of all scored CVEs.
What is the CVSS score of CVE-2026-28490?
CVE-2026-28490 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-28490?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-28490, 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-2026-28490

Explore →

Is Your Infrastructure Affected by CVE-2026-28490?

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

Start Free Scan →Browse All CVEs