CVE-2025-1936: Adding %00 and a fake extension to a jar: URL changed the interpretation of the contents

Published Mar 4, 2025
·
Updated

jar: URLs retrieve local file content packaged in a ZIP archive. The null and everything after it was ignored when retrieving the content from the archive, but the fake extension after the null was used to determine the type of content. This could have been used to hide code in a web extension disguised as something else like an image.

Affected Software

13 affected componentsFixes available
Mozilla Firefox<136
Mozilla Firefox ESR<128.8
Mozilla Firefox ESR<128.8
128.8
Mozilla Firefox<136
136
Mozilla Thunderbird<136
136
debian/firefox
136.0.1-1
debian/firefox-esr<=115.14.0esr-1~deb11u1, <=128.5.0esr-1~deb12u1
128.8.0esr-1~deb11u1128.8.0esr-1~deb12u1128.8.0esr-1
debian/thunderbird<=1:115.12.0-1~deb11u1, <=1:128.5.0esr-1~deb12u1
1:128.8.0esr-1~deb11u11:128.8.0esr-1~deb12u11:128.8.0esr-1
Mozilla Thunderbird<128.8
128.8
Mozilla Firefox<128.8.0
Mozilla Firefox<136.0
Mozilla Thunderbird<128.8.0
Mozilla Thunderbird>=129.0<136.0

Event History

Mar 4, 2025
CVE Published
via Mozilla·12:00 AM
CVE Published
via MITRE·01:31 PM
Data Sourced
via MITRE·01:31 PM
Description
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 PM
Description
Data Sourced
via NVD·02:15 PM
SeverityWeaknessAffected Software
Mar 10, 2025
Data Sourced
via Ubuntu·04:52 PM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2025-1936?

CVE-2025-1936 has a severity rating that indicates it is crucial to address due to potential exploitation.

2

How do I fix CVE-2025-1936?

The fix for CVE-2025-1936 involves updating to Mozilla Firefox version 136 or Firefox ESR version 128.8 or later.

3

What types of software are affected by CVE-2025-1936?

CVE-2025-1936 affects Mozilla Firefox versions up to 136 and Firefox ESR versions up to 128.8.

4

What kind of vulnerability is CVE-2025-1936?

CVE-2025-1936 is a vulnerability that allows local file content retrieval through jar URLs in a ZIP archive.

5

What are the potential risks of CVE-2025-1936?

The potential risks of CVE-2025-1936 include the possibility of code being hidden in web extensions, leading to unauthorized access or manipulation.

Contact

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