CVE-2026-20243
Description
A flaw was found in ClamAV's ALZ file format parser. An unauthenticated, remote attacker can exploit this vulnerability by submitting a specially crafted ALZ (Archived Link Zipped) file for scanning. This improper handling of ALZ files can lead to memory corruption, causing the ClamAV scanning process to terminate. A successful exploit results in a Denial of Service (DoS) condition on the affected software.
Statement
This flaw in ClamAV's ALZ file parser is rated as Important as it allows an unauthenticated, remote attacker to trigger a denial of service. By submitting a specially crafted ALZ file for scanning, an attacker can cause memory corruption, leading to the termination of the ClamAV scanning process. This could disrupt services relying on ClamAV for malware detection in Red Hat environments.
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
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
