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. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

Other sources

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. This vulnerability affects Firefox < 136 and Firefox ESR < 128.8.

— Red Hat

Affected Software

24 affected componentsFixes available
Mozilla Firefox<136
Mozilla Firefox ESR<128.8
Mozilla Thunderbird<136
136
Mozilla Firefox<128.8.0
Mozilla Firefox<136.0
Mozilla Thunderbird<128.8.0
Mozilla Thunderbird>=129.0<136.0
Mozilla Thunderbird<128.8
128.8
ubuntu/mozjs52*
ubuntu/mozjs38*
ubuntu/firefox<136.0+build3-0ubuntu0.20.04.1
136.0+build3-0ubuntu0.20.04.1
ubuntu/mozjs68*
ubuntu/mozjs52*
ubuntu/mozjs102*
ubuntu/mozjs78*
ubuntu/mozjs91*
ubuntu/thunderbird<1:128.12.0+build1-0ubuntu0.22.04.1
1:128.12.0+build1-0ubuntu0.22.04.1
ubuntu/mozjs102*
ubuntu/mozjs115*
Mozilla Firefox ESR<128.8
128.8
Mozilla Firefox<136
136
debian/firefox
159.0.1-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.6.0esr-1~deb12u2140.15.0esr-1~deb13u1153.6.0esr-1~deb13u1153.5.1esr-1153.6.0esr-1
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 to a fixed release to a version that resolves this vulnerability.

    Fixed in 128.8
  3. Upgrade

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

    Fixed in 136.0+build3-0ubuntu0.20.04.1
  4. Upgrade

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

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

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

    Fixed in 136
  6. Upgrade

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

    Fixed in 159.0.1-1
  7. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.6.0esr-1~deb12u2Fixed in 140.15.0esr-1~deb13u1Fixed in 153.6.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.6.0esr-1
  8. 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
  9. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 136
  10. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.8
  11. Upgrade

    Upgrade Thunderbird ESR 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
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
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 OSV·02:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected 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-2025-1936?

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.

Company

Resources

Contact

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