7.5

CVE-2025-5262: mozilla thunderbird Double Free

CVSS: 7.5v3.1HighAnalyzed
AliasesUBUNTU-CVE-2025-5262
Published 27-05-2025Last modified 25-08-2025
Open JSON

Vulnerability summary

CVE-2025-5262 is a high (CVSS 7.5) Double Free vulnerability in mozilla thunderbird. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.6% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.45%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 4 · Related 3
MGASA-2025-0197OPENSUSE-SU-2025:15170-1OPENSUSE-SU-2025:15174-1SUSE-SU-2025:01946-1

Timeline

  1. 27-05-2025
    PublishedVulnerability first disclosed.
  2. 25-08-2025
    Last modifiedVulnerability information updated.

Description

A double-free could have occurred in `vpx_codec_enc_init_multi` after a failed allocation when initializing the encoder for WebRTC. This could have caused memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 139 and Thunderbird < 128.11.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.45%

Chance of exploitation in the next 30 days

Percentile

38%

Versus all other CVEs

30-day change

0.00 pp

From 0.45% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.45%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu6 products
  • mozjs102All versions (No fix recorded)
  • mozjs115All versions (No fix recorded)
  • mozjs52All versions (No fix recorded)
  • mozjs68All versions (No fix recorded)
  • mozjs78All versions (No fix recorded)
Mozilla1 product
  • thunderbird≥ unspecified, < 139 | ≥ unspecified, < 128.11 | < 128.11.0 | < 139.0

2 vendors · 7 products

References

10 links