Bug 2493411 (CVE-2026-14164)

Summary: CVE-2026-14164 libarchive: Double-Free Vulnerability in RAR5 Decompression Logic via dangling filtered_buf pointer in init_unpack()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A double free issue has been identified in libarchive's RAR5 reader. During parsing of a specially crafted RAR5 archive, the filtered_buf pointer may remain stale after being freed during unpacking state reinitialization. Subsequent processing of another archive entry can trigger a second free of the same memory region, resulting in a double-free condition. Successful exploitation may cause applications using the vulnerable libarchive API to terminate unexpectedly, leading to a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2494761, 2494762, 2494763    
Bug Blocks:    

Description OSIDB Bzimport 2026-06-26 13:02:01 UTC 
A double-free vulnerability exists in the libarchive RAR5 reader subsystem within archive_read_support_format_rar5.c where the state tracking pointer rar->cstate.filtered_buf can be linked to a temporary filter output block during archive decompression. When the unpacking engine subsequently processes an adjacent file or resets its internal state layout via init_unpack(), it releases the allocation mapped to filtered_buf but fails to clear or nullify the underlying pointer variable. A specially crafted RAR5 archive can exploit this lingering dangling pointer by forcing a secondary release operation on the exact same memory address, triggering a standard memory-manager abort that immediately crashes the application and results in a Denial of Service (DoS).