Local heap corruption via crafted filename
Published Sep 9, 2022 · Updated Aug 4, 2024
Improper input validation in man2html 1.6g allows local users to cause a service interrupt via a crafted filename. Filename parsing overwrites heap chunk size and linkage fields, then later frees the corrupted chunk with an arbitrary amount of memory. Exploitation requires local file creation and user interaction; the documented consequence is denial of service through memory corruption, with no reported confidentiality or integrity impact.
Summary
What happened
Improper input validation in man2html 1.6g allows local users to cause a service interrupt via a crafted filename. Filename parsing overwrites heap chunk size and linkage fields, then later frees the corrupted chunk with an arbitrary amount of memory. Exploitation requires local file creation and user interaction; the documented consequence is denial of service through memory corruption, with no reported confidentiality or integrity impact.
The record
- CVE
- CVE-2021-40648
- Published
- Sep 9, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-20, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 9, 2022CVE 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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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- CVE-2021-40648 man2html heap corruption PoCproof of concept · unverified
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Technologies
Your stack
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Your stack
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