CVE-2026-20217
Description
A flaw was found in ClamAV. An unauthenticated, remote attacker can exploit a vulnerability in the PESpin file format parser by submitting a specially crafted file. This flaw, caused by improper boundary checks, leads to an out-of-bounds buffer write and memory corruption. A successful exploit can cause the ClamAV scanning process to terminate, resulting in a Denial of Service (DoS) condition on the affected software.
Statement
This is an Important vulnerability in ClamAV's PESpin file format parser. An unauthenticated, remote attacker can exploit improper boundary checks by submitting a specially crafted PESpin file for scanning, leading to an out-of-bounds buffer write and memory corruption. This can cause the ClamAV scanning process to terminate, resulting in a Denial of Service condition.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of the product's implicit security policy. This can often be used to subvert any other security service.
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the product into an infinite loop.
Frequently Asked Questions
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