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
5.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.3Exploit: NoneExposed: 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)
EPSS
5.8%
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(2)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
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.

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 20× 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.

  1. 2026-07-07 04:06 UTCEG score recompute
  2. 2026-07-07 04:06 UTCVendor advisory
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-06 02:05 UTCEG score recompute
  6. 2026-07-06 02:05 UTCVendor advisory
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-05 00:32 UTCEG score recompute
  9. 2026-07-05 00:32 UTCVendor advisory
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-03 22:57 UTCEG score recompute
  12. 2026-07-03 22:57 UTCVendor advisory
  13. 2026-07-02 21:23 UTCEG score recompute
  14. 2026-07-02 21:23 UTCVendor advisory
  15. 2026-07-01 19:50 UTCEG score recompute
  16. 2026-07-01 19:50 UTCVendor advisory
  17. 2026-07-01 15:07 UTCEPSS rescore
  18. 2026-06-30 23:22 UTCEPSS rescore
  19. 2026-06-30 18:16 UTCEG score recompute
  20. 2026-06-30 18:16 UTCVendor advisory
  21. 2026-06-29 16:43 UTCEG score recompute
  22. 2026-06-29 16:43 UTCVendor advisory
  23. 2026-06-29 14:06 UTCEPSS rescore
  24. 2026-06-29 14:06 UTCEPSS rescore
  25. 2026-06-28 15:08 UTCEG score recompute
Show 31 more
  1. 2026-06-28 15:08 UTCVendor advisory
  2. 2026-06-28 14:07 UTCEPSS rescore
  3. 2026-06-28 04:56 UTCEPSS rescore
  4. 2026-06-28 04:56 UTCEPSS rescore
  5. 2026-06-27 13:33 UTCEG score recompute
  6. 2026-06-27 13:33 UTCVendor advisory
  7. 2026-06-27 03:08 UTCEPSS rescore
  8. 2026-06-26 11:59 UTCEG score recompute
  9. 2026-06-25 13:49 UTCEPSS rescore
  10. 2026-06-25 10:26 UTCEG score recompute
  11. 2026-06-24 14:05 UTCEPSS rescore
  12. 2026-06-24 08:52 UTCEG score recompute
  13. 2026-06-23 21:33 UTCEPSS rescore
  14. 2026-06-23 21:33 UTCEPSS rescore
  15. 2026-06-23 07:19 UTCEG score recompute
  16. 2026-06-22 14:25 UTCEPSS rescore
  17. 2026-06-22 14:25 UTCEPSS rescore
  18. 2026-06-22 05:42 UTCEG score recompute
  19. 2026-06-21 14:56 UTCEPSS rescore
  20. 2026-06-21 14:56 UTCEPSS rescore
  21. 2026-06-21 04:08 UTCEG score recompute
  22. 2026-06-21 01:59 UTCEPSS rescore
  23. 2026-06-21 01:59 UTCEPSS rescore
  24. 2026-06-20 02:27 UTCEG score recompute
  25. 2026-06-19 19:26 UTCEPSS rescore
  26. 2026-06-19 19:26 UTCEPSS rescore
  27. 2026-06-19 00:52 UTCEG score recompute
  28. 2026-06-18 17:52 UTCEPSS rescore
  29. 2026-06-18 17:52 UTCEPSS rescore
  30. 2026-06-17 23:17 UTCEG score recompute
  31. 2026-06-17 23:16 UTCNVD updatefirst tracked

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 5.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
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

Explore the affected products and dependency analysis for CVE-2026-48990

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