A Firefox security update has been released for Ubuntu Linux 20.04 LTS.

[USN-6509-1] Firefox vulnerabilities

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Ubuntu Security Notice USN-6509-1
November 23, 2023

firefox vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in Firefox.

Software Description:
- firefox: Mozilla Open Source web browser

Details:

Multiple security issues were discovered in Firefox. If a user were
tricked into opening a specially crafted website, an attacker could
potentially exploit these to cause a denial of service, obtain sensitive
information across domains, or execute arbitrary code. (CVE-2023-6206,
CVE-2023-6210, CVE-2023-6211, CVE-2023-6212, CVE-2023-6213)

It was discovered that Firefox did not properly manage memory when
images were created on the canvas element. An attacker could potentially
exploit this issue to obtain sensitive information. (CVE-2023-6204)

It discovered that Firefox incorrectly handled certain memory when using a
MessagePort. An attacker could potentially exploit this issue to cause a
denial of service. (CVE-2023-6205)

It discovered that Firefox incorrectly did not properly manage ownership
in ReadableByteStreams. An attacker could potentially exploit this issue
to cause a denial of service. (CVE-2023-6207)

It discovered that Firefox incorrectly did not properly manage copy
operations when using Selection API in X11. An attacker could potentially
exploit this issue to obtain sensitive information. (CVE-2023-6208)

Rachmat Abdul Rokhim discovered incorrectly handled parsing of relative
URLS starting with "///". An attacker could potentially exploit this issue
to cause a denial of service. (CVE-2023-6209)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 20.04 LTS:
firefox 120.0+build2-0ubuntu0.20.04.1

After a standard system update you need to restart Firefox to make all the
necessary changes.

References:
https://ubuntu.com/security/notices/USN-6509-1
CVE-2023-6204, CVE-2023-6205, CVE-2023-6206, CVE-2023-6207,
CVE-2023-6208, CVE-2023-6209, CVE-2023-6210, CVE-2023-6211,
CVE-2023-6212, CVE-2023-6213

Package Information:
https://launchpad.net/ubuntu/+source/firefox/120.0+build2-0ubuntu0.20.04.1