CVE-2023-6865
CVE-2023-6865 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 6.5)
- EPSS exploit prediction: 1% (55th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Mozilla Firefox
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2023-6865?
- `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.
- How severe is CVE-2023-6865?
- CVE-2023-6865 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2023-6865 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-6865?
- CVE-2023-6865 primarily affects Mozilla Firefox. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-6865?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2023-6865 published?
- CVE-2023-6865 was published on 2023-12-19 and last updated on 2026-06-17.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1864123
- https://lists.debian.org/debian-lts-announce/2023/12/msg00020.html
- https://security.gentoo.org/glsa/202401-10
- https://www.debian.org/security/2023/dsa-5581
- https://www.mozilla.org/security/advisories/mfsa2023-54/
- https://www.mozilla.org/security/advisories/mfsa2023-56/
Affected products (5)
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*
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