Remote code execution via unallocated placeholder subject
Published Nov 22, 2021 · Updated Aug 4, 2024
Heap overflow in isync mbsync 1.4.0 through 1.4.3 allows remote attackers controlling an IMAP server to execute code via a headerless message. In copy_msg_convert(), a zero-valued break2 offset makes a message beginning with an empty line enter the dummy-subject insertion path without reserving space for that subject. Exploitation requires mbsync to synchronize from a malicious or compromised IMAP server; routine mail delivery adds headers, so an ordinary external sender cannot supply the required headerless form.
Summary
What happened
Heap overflow in isync mbsync 1.4.0 through 1.4.3 allows remote attackers controlling an IMAP server to execute code via a headerless message. In copy_msg_convert(), a zero-valued break2 offset makes a message beginning with an empty line enter the dummy-subject insertion path without reserving space for that subject. Exploitation requires mbsync to synchronize from a malicious or compromised IMAP server; routine mail delivery adds headers, so an ordinary external sender cannot supply the required headerless form.
The record
- CVE
- CVE-2021-44143
- Published
- Nov 22, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 22, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
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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