CVE-2023-6857

Description

When resolving a symlink, a race may occur where the buffer passed to `readlink` may actually be smaller than necessary. *This bug only affects Firefox on Unix-based operating systems (Android, Linux, MacOS). Windows is unaffected.* This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.26%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1796023 issue tracking permissions required
https://www.mozilla.org/security/advisories/mfsa2023-54/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-55/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-56/ vendor advisory
https://www.debian.org/security/2023/dsa-5581 third party advisory
https://www.debian.org/security/2023/dsa-5582 third party advisory
https://lists.debian.org/debian-lts-announce/2023/12/msg00020.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2023/12/msg00021.html third party advisory mailing list
https://security.gentoo.org/glsa/202401-10 third party advisory

Frequently Asked Questions

What is the severity of CVE-2023-6857?
CVE-2023-6857 has been scored as a medium severity vulnerability.
How to fix CVE-2023-6857?
To fix CVE-2023-6857, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-6857 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6857 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-6857?
CVE-2023-6857 affects Mozilla Firefox ESR, Mozilla Thunderbird, Mozilla Firefox.
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