CVE-2025-26695: Downloading of OpenPGP keys from WKD used incorrect padding

Published Mar 4, 2025
·
Updated

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.

Other sources

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 affects Thunderbird < 136 and Thunderbird < 128.8.

— OSV

Affected Software

7 affected componentsFixes available
Mozilla Thunderbird<136, <128.8
Mozilla Thunderbird<136
136
Mozilla Thunderbird<128.8.0
Mozilla Thunderbird>=129.0<136.0
ubuntu/thunderbird<1:128.12.0+build1-0ubuntu0.22.04.1
1:128.12.0+build1-0ubuntu0.22.04.1
Mozilla Thunderbird<128.8
128.8
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.6.0esr-1~deb12u21:140.12.0esr-1~deb13u11:153.6.0esr-1~deb13u11:153.5.0esr-11:153.6.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 136
  2. Upgrade

    Upgrade ubuntu/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:128.12.0+build1-0ubuntu0.22.04.1
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 128.8
  4. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.6.0esr-1~deb12u2Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.6.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.6.0esr-1
  5. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 128.8

Event History

Mar 4, 2025
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Mar 10, 2025
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
CVE Published
via MITRE·06:41 PM
Data Sourced
via MITRE·06:41 PM
Description
Data Sourced
via OSV·07:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·07:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2025-26695?

CVE-2025-26695 is considered a medium severity vulnerability due to the potential exposure of email address lengths to an attacker.

2

How do I fix CVE-2025-26695?

To fix CVE-2025-26695, upgrade to Thunderbird version 136 or later, or version 128.8 or later.

3

What versions of Thunderbird are affected by CVE-2025-26695?

CVE-2025-26695 affects versions of Thunderbird prior to 136 and prior to 128.8.

4

What is the impact of CVE-2025-26695 on user privacy?

The impact of CVE-2025-26695 is that a network observer could potentially learn the length of the requested email address, compromising user privacy.

5

When was CVE-2025-26695 reported?

CVE-2025-26695 was reported as part of security advisories for Mozilla Thunderbird in 2025.

Company

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