Vulnerability · Published Jun 24, 2021 · Assigned by mozilla

CVE-2021-29945

Medium 6.5

In plain English

A medium-severity security flaw in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.2% (higher than 68% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)6.5Medium
Exploit odds (30 days)1.2%top 31.6% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and result in a crash. *Note: This issue only affected x86-32 platforms. Other platforms are unaffected.*. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.20firefox88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.21firefox88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.22firefox88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.23firefox88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.20firefox-esr78.10.0-r0ALPINE-CVE-2021-29945
Alpine:v3.21firefox-esr78.10.0-r0ALPINE-CVE-2021-29945
Alpine:v3.22firefox-esr78.10.0-r0ALPINE-CVE-2021-29945
Alpine:v3.23firefox-esr78.10.0-r0ALPINE-CVE-2021-29945
Alpine:v3.21librewolf88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.22librewolf88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.23librewolf88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.24librewolf88.0-r0ALPINE-CVE-2021-29945
Alpine:v3.20thunderbird91.3.2-r0ALPINE-CVE-2021-29945
Alpine:v3.21thunderbird91.3.2-r0ALPINE-CVE-2021-29945
Alpine:v3.22thunderbird91.3.2-r0ALPINE-CVE-2021-29945
Alpine:v3.23thunderbird91.3.2-r0ALPINE-CVE-2021-29945
Debian:12firefox-esr78.10.0esr-1DEBIAN-CVE-2021-29945
Debian:13firefox-esr78.10.0esr-1DEBIAN-CVE-2021-29945
Debian:14firefox-esr78.10.0esr-1DEBIAN-CVE-2021-29945
Debian:12thunderbird1:78.10.0-1DEBIAN-CVE-2021-29945
Debian:13thunderbird1:78.10.0-1DEBIAN-CVE-2021-29945
Debian:14thunderbird1:78.10.0-1DEBIAN-CVE-2021-29945
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2021-29945

Affected products (as reported)

VendorProductVersions
Mozilla Firefox ESR unspecified – before 78.10
Mozilla Thunderbird unspecified – before 78.10
Mozilla Firefox unspecified – before 88

References