CVE-2021-29945
Mozilla: Incorrect size computation in WebAssembly JIT could lead to null-reads
Severity
ModerateRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · April 19, 2021
Updated · November 22, 2025
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 6.1CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE-476 · NULL Pointer Dereference