Vulnerability · Published Jan 7, 2021 · Assigned by mozilla
CVE-2020-26973
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 1.6% (higher than 76% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)8.8High
Exploit odds (30 days)1.6%top 23.8% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
Certain input to the CSS Sanitizer confused it, resulting in incorrect components being removed. This could have been used as a sanitizer bypass. 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-2020-26973 |
| Alpine:v3.21 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.22 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.23 | firefox | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.20 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.21 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.22 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.23 | firefox-esr | 78.6.0-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.21 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.22 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.23 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.24 | librewolf | 84.0.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.20 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.21 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.22 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26973 |
| Alpine:v3.23 | thunderbird | 78.6.1-r0 | ALPINE-CVE-2020-26973 |
| Debian:12 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26973 |
| Debian:13 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26973 |
| Debian:14 | firefox-esr | 78.6.0esr-1 | DEBIAN-CVE-2020-26973 |
| Debian:12 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26973 |
| Debian:13 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26973 |
| Debian:14 | thunderbird | 1:78.6.0-1 | DEBIAN-CVE-2020-26973 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2020-26973 |
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=1680084 x_refsource_MISC