CVE-2023-3417
CVE-2023-3417 is a high-severity vulnerability in Mozilla Thunderbird with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 1% (42nd percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Mozilla Thunderbird
- Published:
- Last modified:
Description
Thunderbird allowed the Text Direction Override Unicode Character in filenames. An email attachment could be incorrectly shown as being a document file, while in fact it was an executable file. Newer versions of Thunderbird will strip the character and show the correct file extension. This vulnerability affects Thunderbird < 115.0.1 and Thunderbird < 102.13.1.
Frequently asked questions
- What is CVE-2023-3417?
- Thunderbird allowed the Text Direction Override Unicode Character in filenames. An email attachment could be incorrectly shown as being a document file, while in fact it was an executable file. Newer versions of Thunderbird will strip the character and show the correct file extension. This vulnerability affects Thunderbird < 115.0.1 and Thunderbird < 102.13.1.
- How severe is CVE-2023-3417?
- CVE-2023-3417 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
- Is CVE-2023-3417 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-3417?
- CVE-2023-3417 primarily affects Mozilla Thunderbird. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-3417?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-3417 published?
- CVE-2023-3417 was published on 2023-07-24 and last updated on 2026-06-17.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1835582
- https://lists.debian.org/debian-lts-announce/2023/07/msg00032.html
- https://www.debian.org/security/2023/dsa-5463
- https://www.mozilla.org/security/advisories/mfsa2023-27/
- https://www.mozilla.org/security/advisories/mfsa2023-28/
Affected products (4)
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
- 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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