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Vulnerability Intelligence

CVE-2020-12420

HIGH8.8

When trying to connect to a STUN server, a race condition could have caused a use-after-free of a pointer, leading to memory corruption and a potentially exploitable crash

Published Jul 9, 2020

Modified 1 years ago

Fix available

Details

When trying to connect to a STUN server, a race condition could have caused a use-after-free of a pointer, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.

Affected Packages

Ubuntu:14.04:LTSFirefox

Fixed in:

78

Ubuntu:16.04:LTSFirefox

Fixed in:

78

Ubuntu:18.04:LTSFirefox

Fixed in:

78

Ubuntu:20.04:LTSFirefox

Fixed in:

78

Ubuntu:22.04:LTSFirefox

Fixed in:

78

Ubuntu:24.04:LTSFirefox

Fixed in:

78

Ubuntu:25.04Firefox

Fixed in:

78

Ubuntu:25.10Firefox

Fixed in:

78

Windows:10240Mozilla Firefox

Fixed in:

78

Windows:10240Mozilla Firefox ESR

Fixed in:

68.10

Windows:14393Mozilla Firefox

Fixed in:

78

Windows:14393Mozilla Firefox ESR

Fixed in:

68.10

Windows:17763Mozilla Firefox

Fixed in:

78

Windows:17763Mozilla Firefox ESR

Fixed in:

68.10

Windows:18362Mozilla Firefox

Fixed in:

78

Windows:18362Mozilla Firefox ESR

Fixed in:

68.10

Windows:18363Mozilla Firefox

Fixed in:

78

Windows:18363Mozilla Firefox ESR

Fixed in:

68.10

Windows:19041Mozilla Firefox

Fixed in:

78

Windows:19041Mozilla Firefox ESR

Fixed in:

68.10

Windows:19042Mozilla Firefox

Fixed in:

78

Windows:19042Mozilla Firefox ESR

Fixed in:

68.10

Windows:19043Mozilla Firefox

Fixed in:

78

Windows:19043Mozilla Firefox ESR

Fixed in:

68.10

Windows:19044Mozilla Firefox

Fixed in:

78

Windows:19044Mozilla Firefox ESR

Fixed in:

68.10

Windows:19045Mozilla Firefox

Fixed in:

78

Windows:19045Mozilla Firefox ESR

Fixed in:

68.10

Windows:20348Mozilla Firefox

Fixed in:

78

Windows:20348Mozilla Firefox ESR

Fixed in:

68.10

Windows:22000Mozilla Firefox

Fixed in:

78

Windows:22000Mozilla Firefox ESR

Fixed in:

68.10

Windows:22621Mozilla Firefox

Fixed in:

78

Windows:22621Mozilla Firefox ESR

Fixed in:

68.10

Windows:22631Mozilla Firefox

Fixed in:

78

Windows:22631Mozilla Firefox ESR

Fixed in:

68.10

Windows:25398Mozilla Firefox

Fixed in:

78

Windows:25398Mozilla Firefox ESR

Fixed in:

68.10

Windows:26100Mozilla Firefox

Fixed in:

78

Windows:26100Mozilla Firefox ESR

Fixed in:

68.10

Windows:26200Mozilla Firefox

Fixed in:

78

Windows:26200Mozilla Firefox ESR

Fixed in:

68.10

macOS:14Firefox

Fixed in:

78

macOS:14Firefox ESR

Fixed in:

68.10

macOS:15Firefox

Fixed in:

78

macOS:15Firefox ESR

Fixed in:

68.10

macOS:26Firefox

Fixed in:

78

macOS:26Firefox ESR

Fixed in:

68.10

References

ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.html ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.html ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html ADVISORYhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html WEBhttps://bugzilla.mozilla.org/show_bug.cgi?id=1643437 ADVISORYhttps://security.gentoo.org/glsa/202007-09 ADVISORYhttps://security.gentoo.org/glsa/202007-10 ADVISORYhttps://usn.ubuntu.com/4421-1/ADVISORYhttps://www.cve.org/CVERecord?id=CVE-2020-12420 WEBhttps://www.mozilla.org/security/advisories/mfsa2020-24/WEBhttps://www.mozilla.org/security/advisories/mfsa2020-25/WEBhttps://www.mozilla.org/security/advisories/mfsa2020-26/

CVSS Analysis

CVSS v3.1

8.8

Exploitability

Attack Vector

NetworkAV:N

Attack Complexity

LowAC:L

Privileges Required

NonePR:N

User Interaction

RequiredUI:R

Scope

Scope

UnchangedS:U

Impact

Confidentiality

HighC:H

Integrity

HighI:H

Availability

HighA:H

8.8/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Ecosystems

Ubuntu 14.04 LTS Ubuntu 16.04 LTS Ubuntu 18.04 LTS Ubuntu 20.04 LTS Ubuntu 22.04 LTS Ubuntu 24.04 LTS Ubuntu 25.04 Ubuntu 25.10 Windows 10 (1507)Windows 10 (1607) / Server 2016 Windows 10 (1809) / Server 2019 Windows 10 (1903)Windows 10 (1909)Windows 10 (2004)Windows 10 (20H2)Windows 10 (21H1)Windows 10 (21H2)Windows 10 (22H2)Windows Server 2022 Windows 11 (21H2)Windows 11 (22H2)Windows 11 (23H2)Windows Server 2025 Windows 11 (24H2)Windows Server 2025 macOS 14 macOS 15 macOS 26

Timeline

PublishedJul 9, 2020

ModifiedAug 4, 2024

CVE-2020-12420 | Mondoo Vulnerability Intelligence