CVE-2026-48990

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 94% 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 — 3 sources updated this week
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

A fix is available — apply it.

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. In versions 1.3.4 through 1.6.5, joserfc accepts oversized RFC7797 b64=false JWS payloads without applying JWSRegistry.max_payload_length, which can lead to resource exhaustion. The normal JWS compact and flattened JSON paths reject payloads above the configured payload-size limit with ExceededSizeError. The RFC7797 unencoded payload paths do not make the same check. A valid b64=false compact or flattened JSON JWS can therefore deserialize successfully with a payload larger than JWSRegistry.max_payload_length. Applications that accept lower-trust JWS values and rely on joserfc to reject oversized token content during verification have a moderate availability risk. This issue has been fixed in version 1.6.7.

CVSS v3
5.3
EG Score
5.3(medium)
EG Risk
28(Track)
EG Risk 28/100SSVC: 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
Severity53% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
6%
KEV
Not listed

Published

June 17, 2026

Last Modified

June 23, 2026

Advisory Details (2)

Auto-updated Jun 17, 2026
🔬 Proof of concept available. Patch available. Sources: github_release, github.
github Patch Available🟡 PoC Available

RFC7797 b64=false JWS payloads bypass JWSRegistry payload-size limits during deserialization · Advisory · authlib/joserfc · GitHub

https://github.com/authlib/joserfc/security/advisories/GHSA-wphv-vfrh-23q5
github_release Patch Available

1.6.7

Patch available: authlib/joserfc 1.6.7

https://github.com/authlib/joserfc/releases/tag/1.6.7

Vendor Advisories for CVE-2026-48990(5)

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

Patch Availability(4)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatansible-automation-platform-26/lightspeed-chatbot-rhel9:17856461882026-08-04redhat
redhatansible-automation-platform-27/lightspeed-chatbot-rhel9:17854267342026-08-04redhat
redhatmta/mta-solution-server-rhel9:17841098832026-07-21redhat
redhatjaeger-main-2.19.0-1.hum12026-06-10redhat

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.

Affected Packages

(3 across 3 ecosystems)
Debian:13(1)
PackageVulnerable rangeFixed inDependents
joserfc1.1.0-1 ... 1.7.4-1 (22 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
joserfc1.1.0-1 ... 1.6.5-1 (16 versions)1.6.8-1—
PyPI(1)
PackageVulnerable rangeFixed inDependents
joserfc1.3.4 ... 1.6.5 (13 versions)1.6.7—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 56× 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 154 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-48990?
CVE-2026-48990 is a medium vulnerability published on June 17, 2026. joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. In versions 1.3.4 through 1.6.5, joserfc accepts oversized RFC7797 b64=false JWS payloads without applying JWSRegistry.maxpayloadlength, which can lead to resource exhaustion.…
When was CVE-2026-48990 disclosed?
CVE-2026-48990 was first published in the National Vulnerability Database on June 17, 2026, with the most recent update on June 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48990 actively exploited?
CVE-2026-48990 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 94.2% of all scored CVEs.
What is the CVSS score of CVE-2026-48990?
CVE-2026-48990 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-48990?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48990, 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-2026-48990

Explore →

Is Your Infrastructure Affected by CVE-2026-48990?

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

Start Free Scan →Browse All CVEs