9.1

CVE-2025-54887: jwe: Missing AES-GCM authentication tag validation in encrypted JWEs

Deferred
AliasesGHSA-c7p4-hx26-pr73
Published 08-08-2025Last modified 08-08-2025

Vulnerability summary

CVE-2025-54887 is a critical (CVSS 9.1) vulnerability in jwt ruby-jwe. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 19% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 9.1 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.27%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 08-08-2025
    PublishedVulnerability first disclosed.
  2. 08-08-2025
    Last modifiedVulnerability information updated.

Description

jwe is a Ruby implementation of the RFC 7516 JSON Web Encryption (JWE) standard. In versions 1.1.0 and below, authentication tags of encrypted JWEs can be brute forced, which may result in loss of confidentiality for those JWEs and provide ways to craft arbitrary JWEs. This puts users at risk because JWEs can be modified to decrypt to an arbitrary value, decrypted by observing parsing differences and the GCM internal GHASH key can be recovered. Users are affected by this vulnerability even if they do not use an AES-GCM encryption algorithm for their JWEs. As the GHASH key may have been leaked, users must rotate the encryption keys after upgrading. This issue is fixed in version 1.1.1.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.27%

Chance of exploitation in the next 30 days

Percentile

19%

Versus all other CVEs

30-day change

Increase +0.01 pp

From 0.25% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Jwt1 product
RubyGems1 product
  • jwe< 1.1.1

2 vendors · 2 products

References

5 links