CVE-2013-1055: Potential DoS through abuse of rate limit in libunity-webapps for Firefox

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-04-07 · updated 2026-06-16
Weakness: CWE-404

Description

The unity-firefox-extension package could be tricked into dropping a C callback which was still in use, which Firefox would then free, causing Firefox to crash. This could be achieved by adding an action to the launcher and updating it with new callbacks until the libunity-webapps rate limit was hit. Fixed in 3.0.0+14.04.20140416-0ubuntu1.14.04.1 of unity-firefox-extension and in all versions of libunity-webapps by shipping an empty unity-firefox-extension package, thus disabling the extension entirely and invalidating the attack against the libunity-webapps package.

Affected products

Canonical Ubuntu Linux: 14.04, 15.04
Canonical unity-firefox-extension: before 3.0.0\+14.04.20140416-0ubuntu1.14.04.1 — fixed in 3.0.0\+14.04.20140416-0ubuntu1.14.04.1

How to fix

Upgrade to a fixed version: Canonical unity-firefox-extension 3.0.0\+14.04.20140416-0ubuntu1.14.04.1. Check the vendor advisory for mitigations.

References

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