Vulnerability · Published Jan 7, 2021 · Assigned by mozilla
CVE-2020-26974
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 1.5% (higher than 75% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)8.8High
Exploit odds (30 days)1.5%top 25.1% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
When flex-basis was used on a table wrapper, a StyleGenericFlexBasis object could have been incorrectly cast to the wrong type. This resulted in a heap user-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.21 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.22 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.23 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.20 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.21 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.22 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.23 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.21 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.22 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.23 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.24 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.20 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.21 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.22 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26974 |
| Alpine:v3.23 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26974 |
| Debian:12 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26974 |
| Debian:13 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26974 |
| Debian:14 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26974 |
| Debian:12 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26974 |
| Debian:13 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26974 |
| Debian:14 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26974 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2020-26974 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | unspecified – before 84 |
| Mozilla | Thunderbird | unspecified – before 78.6 |
| Mozilla | Firefox ESR | unspecified – before 78.6 |
References
- https://www.mozilla.org/security/advisories/mfsa2020-54/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2020-56/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2020-55/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1681022 x_refsource_MISC