Process crash via unterminated mailbox constraint buffer
Published Sep 24, 2021 · Updated Aug 4, 2024
Out-of-bounds read in LibreSSL through 3.4.0 allows context-dependent attackers to crash a process via an overlong mailbox constraint. x509_constraints_parse_mailbox accepts DOMAIN_PART_MAX_LEN bytes into working because it checks > instead of >=, then strdup reads past the unterminated buffer. Reachability requires an application to parse an attacker-controlled X.509 mailbox name constraint; the demonstrated consequence is a process crash.
Summary
What happened
Out-of-bounds read in LibreSSL through 3.4.0 allows context-dependent attackers to crash a process via an overlong mailbox constraint. x509_constraints_parse_mailbox accepts DOMAIN_PART_MAX_LEN bytes into working because it checks > instead of >=, then strdup reads past the unterminated buffer. Reachability requires an application to parse an attacker-controlled X.509 mailbox name constraint; the demonstrated consequence is a process crash.
The record
- CVE
- CVE-2021-41581
- Published
- Sep 24, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125, T1499
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 24, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- x509_constraints_parse_mailbox crash reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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