Skip to content
Fencer Intel
high 7.5

CVE-2025-63811 json

jose2go is vulnerable to a JWT bomb attack through its decode function

published 11mo ago modified 4d ago also GHSA-9mj6-hxhv-w67j , GO-2025-4123 , EUVD-2025-131963

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits
0
none known

Summary

An issue was discovered in dvsekhvalnov jose2go 1.5.0 thru 1.7.0 allowing an attacker to cause a Denial-of-Service (DoS) via crafted JSON Web Encryption (JWE) token with an exceptionally high compression ratio.

Patch / fix

  • go github.com/dvsekhvalnov/jose2go 1.7.0
  • dvsekhvalnov jose2go 1.7.0
  • golang-github-dvsekhvalnov-jose2go Debian 14 1.9-1

debian advisories DEBIAN-CVE-2025-63811

  • govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1

opensuse advisories openSUSE-SU-2026:21483-1

Is CVE-2025-63811 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-63811 updated cvss 7.5

jose2go: jose2go: Denial-of-Service via crafted JWE token

  • Red Hat Multicluster Engine for Kubernetes multicluster-engine/cluster-api-provider-aws-rhel9
    affected: no fix available

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
11mo ago

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/dvsekhvalnov/jose2go/issues/33 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
go github.com/dvsekhvalnov/jose2go
<1.7.0
1.7.0

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.