CVE-2021-29946: Integer Overflow

Published Apr 19, 2021
·
Updated

Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header.

Affected Software

9 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<78.10
78.10
Mozilla Firefox<88.0
Mozilla Firefox ESR<78.10
Mozilla Thunderbird<78.10
Mozilla Firefox<88
88
Mozilla Firefox ESR<78.10
78.10

Event History

Apr 19, 2021
CVE Published
via Mozilla·12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:19 PM
Data Sourced
via MITRE·01:19 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2021-29946.

2

What is the severity of CVE-2021-29946?

The severity of CVE-2021-29946 is low.

3

Which software products are affected by CVE-2021-29946?

Mozilla Thunderbird 78.10, Mozilla Firefox ESR 78.10, and Mozilla Firefox up to version 88 are affected by CVE-2021-29946.

4

What could happen due to CVE-2021-29946?

CVE-2021-29946 could result in the bypassing of port blocking restrictions when certain ports are used in the Alt-Svc header.

5

Where can I find more information about CVE-2021-29946?

More information about CVE-2021-29946 can be found at the following references: [1](https://bugzilla.mozilla.org/show_bug.cgi?id=1698503), [2](https://www.mozilla.org/en-US/security/advisories/mfsa2021-14/), [3](https://www.mozilla.org/en-US/security/advisories/mfsa2021-16/).

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