Client hang via unchecked GPGME read error
Published May 4, 2026 · Updated May 4, 2026
Infinite-loop denial of service in Mutt before 2.3.2 allows remote attackers to hang the client through GPGME data processing. The data_object_to_stream function treats a gpgme_data_read return value of -1 as loop progress and writes to the output stream with that negative length. Reaching the flaw requires Mutt's GPGME-backed cryptography path to encounter a read error; the client then consumes resources without exiting the loop.
Summary
What happened
Infinite-loop denial of service in Mutt before 2.3.2 allows remote attackers to hang the client through GPGME data processing. The data_object_to_stream function treats a gpgme_data_read return value of -1 as loop progress and writes to the output stream with that negative length. Reaching the flaw requires Mutt's GPGME-backed cryptography path to encounter a read error; the client then consumes resources without exiting the loop.
The record
- CVE
- CVE-2026-43863
- Published
- May 4, 2026
- Updated
- May 4, 2026
- Vendor
- Mutt
- Product
- Mutt
- Classifications
- CWE-253, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 4, 2026CVE publishedPublication date reported by the CVE source.
- May 4, 2026Record 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=0 <2.3.2
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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