Unauthenticated server crash via MIME lookup overread
Published Jan 29, 2026 · Updated Jan 29, 2026
An out-of-bounds read in Monkey through commit f37e984 allows remote attackers to crash the HTTP server with a crafted request. The mk_mimetype_find function in mk_server/mk_mimetype.c reads beyond its valid buffer while resolving a request's MIME type. No authentication or user interaction is required, and the reported consequence is service interruption rather than data disclosure or modification.
Summary
What happened
An out-of-bounds read in Monkey through commit f37e984 allows remote attackers to crash the HTTP server with a crafted request. The mk_mimetype_find function in mk_server/mk_mimetype.c reads beyond its valid buffer while resolving a request's MIME type. No authentication or user interaction is required, and the reported consequence is service interruption rather than data disclosure or modification.
The record
- CVE
- CVE-2025-63657
- Published
- Jan 29, 2026
- Updated
- Jan 29, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 29, 2026CVE publishedPublication date reported by the CVE source.
- Jan 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
- monkey-poc.zipproof of concept · unverified
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Technologies
Your stack
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Your stack
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