Vulnerability · Published Dec 19, 2023 · Assigned by mozilla

CVE-2023-6865

Medium 6.5

In plain English

A medium-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 0.9% (higher than 59% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)6.5Medium
Exploit odds (30 days)0.9%top 40.5% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

`EncryptingOutputStream` was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode. This vulnerability affects Firefox ESR < 115.6 and Firefox < 121.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8firefox115.6.0-1.el8_9.almaALSA-2024:0012
AlmaLinux:9firefox115.6.0-1.el9_3.almaALSA-2024:0025
AlmaLinux:9firefox-x11115.6.0-1.el9_3.almaALSA-2024:0025
Alpine:v3.20firefox-esr115.6.0-r0ALPINE-CVE-2023-6865
Alpine:v3.21firefox-esr115.6.0-r0ALPINE-CVE-2023-6865
Alpine:v3.22firefox-esr115.6.0-r0ALPINE-CVE-2023-6865
Alpine:v3.23firefox-esr115.6.0-r0ALPINE-CVE-2023-6865
Debian:12firefox-esr115.6.0esr-1~deb12u1DEBIAN-CVE-2023-6865
Debian:12firefox-esr115.6.0esr-1~deb12u1DSA-5581-1
Debian:13firefox-esr115.6.0esr-1DEBIAN-CVE-2023-6865
Debian:14firefox-esr115.6.0esr-1DEBIAN-CVE-2023-6865
Rocky Linux:8firefox0:115.6.0-1.el8_9RLSA-2024:0012
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2023-6865
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2023-6865
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2023-6865
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2023-6865

Affected products (as reported)

VendorProductVersions
Mozilla Firefox ESR unspecified – before 115.6
Mozilla Firefox unspecified – before 121

References