synced 12 MIN AGO
01 Record

CVE-2026-48990

joserfc: b64=false RFC7797 JWS payloads bypass JWSRegistry payload-size limits during deserialization

MediumPUBLISHEDCNA: GitHub_M
CNA base score5.3 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

02 Description

joserfc: b64=false RFC7797 JWS payloads bypass JWSRegistry payload-size limits during deserialization

03 Exploitation and scoring

Exploitation
Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
SSVC decision
  • ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
  • AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
  • Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.16% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 5.4% of scored records. A rank, not a probability.
NVD base score
5.3 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD analysis status
Deferred. NVD last modified this record on 2026-10-26.
Red Hat severity
Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-06-17 21:08Z4 MO AGO
Last updated
2026-06-18 12:51Z4 MO AGO
Reserved
2026-05-26
Assigning CNA
GitHub_M
Record state
PUBLISHED
Severity
Medium (CVSS 5.3)
CNA CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weaknesses
  • CWE-400Uncontrolled Resource ConsumptionClass
  • CWE-770Allocation of Resources Without Limits or ThrottlingBase
Data version
5.2
Document digest
36f939c8c8c89d7721850f2187fb5cf4c226e049d08a31e80292d8a46e29d002

05 Affected products

VendorProductVersionsPlatforms
authlibjoserfc< 1.6.7—

06 References

07 Fixed in

Debian 13

  • joserfc
    No fix yet

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

  • joserfc
    Fixed in 1.6.8-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 25.10

  • joserfc
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.04 LTS

  • joserfc
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.