Vulnerability · Published Aug 17, 2021 · Assigned by mozilla
CVE-2021-29981
High 8.8
In plain English
A high-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 1.0% (higher than 63% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)8.8High
Exploit odds (30 days)1.0%top 36.6% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
An issue present in lowering/register allocation could have led to obscure but deterministic register confusion failures in JITted code that would lead to a potentially exploitable crash. This vulnerability affects Firefox < 91 and Thunderbird < 91.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.21 | firefox | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.22 | firefox | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.23 | firefox | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.21 | librewolf | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.22 | librewolf | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.23 | librewolf | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.24 | librewolf | 92.0.1-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.20 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.21 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.22 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-29981 |
| Alpine:v3.23 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-29981 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2021-29981 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | unspecified – before 91 |
| Mozilla | Thunderbird | unspecified – before 91 |
References
- https://www.mozilla.org/security/advisories/mfsa2021-33/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-36/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1707774 x_refsource_MISC
- GLSA-202202-03 vendor-advisory, x_refsource_GENTOO