Local service crash via oversized working directory
Published May 6, 2021 · Updated Aug 4, 2024
Out-of-bounds write in Exim 4.92 through 4.94.1 allows local users to crash a setuid-root process via a long path. In main(), Exim copies initial_cwd into a 16 KB heap buffer, advances the pointer by the untruncated pathname length, and writes beyond the allocation. A local user must create a deeply nested working directory and invoke Exim; the published proof of concept causes a segmentation fault, while root privilege escalation was not demonstrated.
Summary
What happened
Out-of-bounds write in Exim 4.92 through 4.94.1 allows local users to crash a setuid-root process via a long path. In main(), Exim copies initial_cwd into a 16 KB heap buffer, advances the pointer by the untruncated pathname length, and writes beyond the allocation. A local user must create a deeply nested working directory and invoke Exim; the published proof of concept causes a segmentation fault, while root privilege escalation was not demonstrated.
The record
- CVE
- CVE-2020-28010
- Published
- May 6, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 6, 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.
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
- Qualys CVE-2020-28010 crash proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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