Vulnerability · Published Jun 24, 2021 · Assigned by mozilla
CVE-2021-23999
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 1.4% (higher than 72% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)8.8High
Exploit odds (30 days)1.4%top 27.9% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | firefox | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.21 | firefox | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.22 | firefox | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.23 | firefox | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.20 | firefox-esr | 78.10.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.21 | firefox-esr | 78.10.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.22 | firefox-esr | 78.10.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.23 | firefox-esr | 78.10.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.21 | librewolf | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.22 | librewolf | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.23 | librewolf | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.24 | librewolf | 88.0-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.20 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.21 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.22 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-23999 |
| Alpine:v3.23 | thunderbird | 91.3.2-r0 | ALPINE-CVE-2021-23999 |
| Debian:12 | firefox-esr | 78.10.0esr-1 | DEBIAN-CVE-2021-23999 |
| Debian:13 | firefox-esr | 78.10.0esr-1 | DEBIAN-CVE-2021-23999 |
| Debian:14 | firefox-esr | 78.10.0esr-1 | DEBIAN-CVE-2021-23999 |
| Debian:12 | thunderbird | 1:78.10.0-1 | DEBIAN-CVE-2021-23999 |
| Debian:13 | thunderbird | 1:78.10.0-1 | DEBIAN-CVE-2021-23999 |
| Debian:14 | thunderbird | 1:78.10.0-1 | DEBIAN-CVE-2021-23999 |
| Ubuntu:22.04:LTS | mozjs78 | no fix listed | UBUNTU-CVE-2021-23999 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox ESR | unspecified – before 78.10 |
| Mozilla | Thunderbird | unspecified – before 78.10 |
| Mozilla | Firefox | unspecified – before 88 |
References
- https://www.mozilla.org/security/advisories/mfsa2021-14/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-16/ x_refsource_MISC
- https://www.mozilla.org/security/advisories/mfsa2021-15/ x_refsource_MISC
- https://bugzilla.mozilla.org/show_bug.cgi?id=1691153 x_refsource_MISC