CVE-2020-12387

Mozilla: Use-after-free during worker shutdown

Severity Score

8.1

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

Una condición de carrera cuando se ejecuta el código shutdown para Web Worker conllevo a una vulnerabilidad de uso de la memoria previamente liberada. Esto resultó en un bloqueo potencialmente explotable. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 68.8, Firefox versiones anteriores a 76 y Thunderbird versiones anteriores a 68.8.0.

A flaw was found in Mozilla Firefox and Thunderbird. When running shutdown code for Web Worker, a race condition occurs leading to a use-after-free memory flaw that could lead to an exploitable crash. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

*Credits: N/A

CVSS Scores

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-04-28 CVE Reserved
2020-05-06 CVE Published
2024-08-04 CVE Updated
2024-09-19 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CWE-416: Use After Free

CAPEC

References (8)

URL	Tag	Source
https://security.gentoo.org/glsa/202005-03	Third Party Advisory
https://security.gentoo.org/glsa/202005-04	Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-16	Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-17	Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-18	Third Party Advisory

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://usn.ubuntu.com/4373-1	2021-12-14
https://access.redhat.com/security/cve/CVE-2020-12387	2020-05-11
https://bugzilla.redhat.com/show_bug.cgi?id=1831761	2020-05-11

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Mozilla Search vendor "Mozilla"		Firefox Search vendor "Mozilla" for product "Firefox"				< 76.0 Search vendor "Mozilla" for product "Firefox" and version " < 76.0"		-		Affected
Mozilla Search vendor "Mozilla"		Firefox Esr Search vendor "Mozilla" for product "Firefox Esr"				< 68.8.0 Search vendor "Mozilla" for product "Firefox Esr" and version " < 68.8.0"		-		Affected
Mozilla Search vendor "Mozilla"		Thunderbird Search vendor "Mozilla" for product "Thunderbird"				< 68.8.0 Search vendor "Mozilla" for product "Thunderbird" and version " < 68.8.0"		-		Affected