5.3

CVE-2025-26695: mozilla thunderbird

CVSS: 5.3v3.1MediumModified
AliasesUBUNTU-CVE-2025-26695DEBIAN-CVE-2025-26695
Published 10-03-2025Last modified 13-04-2026
Open JSON

Vulnerability summary

CVE-2025-26695 is a medium (CVSS 5.3) vulnerability in mozilla thunderbird. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 4.3% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.16%
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 13 · Related 2
DLA-4081-1DSA-5876-1RHSA-2025:2899RHSA-2025:2900RHSA-2025:2957RHSA-2025:2958

Timeline

  1. 10-03-2025
    PublishedVulnerability first disclosed.
  2. 13-04-2026
    Last modifiedVulnerability information updated.

Description

When requesting an OpenPGP key from a WKD server, an incorrect padding size was used and a network observer could have learned the length of the requested email address. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.16%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

0.00 pp

From 0.15% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.16%

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

No weakness data has been published for this record.

Affected systems

Debian1 product
  • thunderbird< 1:128.8.0esr-1~deb12u1 | < 1:128.8.0esr-1
Mozilla1 product
Ubuntu1 product
  • thunderbird< 1:128.12.0+build1-0ubuntu0.22.04.1

3 vendors · 3 products

References

8 links