Reflected file download via NULL-byte filename truncation
Published Jun 2, 2023 · Updated Jan 9, 2025
Reflected file download in Mozilla Firefox before 112 allows remote attackers to trick users into installing malware via crafted Content-Disposition headers. The filename parser truncates names at a NULL character, so a server-supplied dangerous extension can replace the intended suffix during download handling. Exploitation requires a victim to visit an attacker-controlled or compromised site and accept the resulting download; the flaw does not independently execute code.
Summary
What happened
Reflected file download in Mozilla Firefox before 112 allows remote attackers to trick users into installing malware via crafted Content-Disposition headers. The filename parser truncates names at a NULL character, so a server-supplied dangerous extension can replace the intended suffix during download handling. Exploitation requires a victim to visit an attacker-controlled or compromised site and accept the resulting download; the flaw does not independently execute code.
The record
- CVE
- CVE-2023-29539
- Published
- Jun 2, 2023
- Updated
- Jan 9, 2025
- Vendor
- Mozilla
- Product
- Firefox
- Classifications
- CWE-476, T1204.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 2, 2023CVE publishedPublication date reported by the CVE source.
- Jan 9, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=unspecified <112
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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