CVE-2023-6209

Description

Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.43%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Firefox ESR
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1858570 issue tracking permissions required
https://www.mozilla.org/security/advisories/mfsa2023-49/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-50/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-52/ release notes vendor advisory
https://www.debian.org/security/2023/dsa-5561 third party advisory
https://lists.debian.org/debian-lts-announce/2023/11/msg00017.html mailing list
https://lists.debian.org/debian-lts-announce/2023/11/msg00030.html

Frequently Asked Questions

What is the severity of CVE-2023-6209?
CVE-2023-6209 has been scored as a medium severity vulnerability.
How to fix CVE-2023-6209?
To fix CVE-2023-6209, 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-2023-6209 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-6209 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-2023-6209?
CVE-2023-6209 affects Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird.
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