Vulnerability · Published Nov 3, 2021 · Assigned by mozilla
CVE-2021-38496
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 1.7% (higher than 77% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)8.8High
Exploit odds (30 days)1.7%top 23.2% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.21 | firefox | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.22 | firefox | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.23 | firefox | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.20 | firefox-esr | 91.2.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.21 | firefox-esr | 91.2.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.22 | firefox-esr | 91.2.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.23 | firefox-esr | 91.2.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.21 | librewolf | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.22 | librewolf | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.23 | librewolf | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.24 | librewolf | 93.0-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.20 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.21 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.22 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-38496 |
| Alpine:v3.23 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-38496 |
| Debian:12 | firefox-esr | 91.2.0esr-1 | DEBIAN-CVE-2021-38496 |
| Debian:13 | firefox-esr | 91.2.0esr-1 | DEBIAN-CVE-2021-38496 |
| Debian:14 | firefox-esr | 91.2.0esr-1 | DEBIAN-CVE-2021-38496 |
| Debian:12 | thunderbird | 1:91.2.1-1 | DEBIAN-CVE-2021-38496 |
| Debian:13 | thunderbird | 1:91.2.1-1 | DEBIAN-CVE-2021-38496 |
| Debian:14 | thunderbird | 1:91.2.1-1 | DEBIAN-CVE-2021-38496 |
| Rocky Linux:8 | firefox | 0:91.2.0-4.el8_4 | RLSA-2021:3755 |
| Rocky Linux:8 | thunderbird | 0:91.2.0-1.el8_4 | RLSA-2021:3838 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2021-38496 |
| Ubuntu:22.04:LTS | thunderbird | 1:91.3.0+build2-0ubuntu1 | UBUNTU-CVE-2021-38496 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Thunderbird | unspecified – before 78.15unspecified – before 91.2 |
| Mozilla | Firefox ESR | unspecified – before 91.2unspecified – before 78.15 |
| Mozilla | Firefox | unspecified – before 93 |
References
- https://www.mozilla.org/security/advisories/mfsa2021-47/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-45/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-43/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-46/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-44/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1725335 x_refsource_MISC
- DSA-5034 vendor-advisory, x_refsource_DEBIAN
- [debian-lts-announce] 20220104 [SECURITY] [DLA 2874-1] thunderbird security update mailing-list, x_refsource_MLIST