Process crash via overflowing ACL resize calculation
Published Jul 6, 2021 · Updated Aug 3, 2024
Integer overflow in pywin32 before 301 allows remote authenticated users with ACL access to crash a vulnerable process. PyACL permits required_size to wrap while enlarging an ACL, allocates an undersized heap buffer, and copies existing ACL data beyond that allocation. Exploitation requires access to the target object's ACL and enough ACE additions to exceed 65,535 bytes; the demonstrated consequence is a hosting-process crash.
Summary
What happened
Integer overflow in pywin32 before 301 allows remote authenticated users with ACL access to crash a vulnerable process. PyACL permits required_size to wrap while enlarging an ACL, allocates an undersized heap buffer, and copies existing ACL data beyond that allocation. Exploitation requires access to the target object's ACL and enough ACE additions to exceed 65,535 bytes; the demonstrated consequence is a hosting-process crash.
The record
- CVE
- CVE-2021-32559
- Published
- Jul 6, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190, T1499
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 6, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
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
- PyACL oversized ACL reproduction procedureproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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