Bug 2511585 (CVE-2026-71267)

Summary: CVE-2026-71267 microtar: microtar: Stack buffer overflow via overly long filenames
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in microtar. The mtar_write_file_header() and mtar_write_dir_header() functions copy a caller-supplied entry name into a fixed 100-byte stack buffer using strcpy() without validating the name length. An application that archives an attacker-controlled or externally supplied filename longer than 99 characters can trigger a stack buffer overflow, which could lead to arbitrary code execution or denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2511897, 2511898    
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Description OSIDB Bzimport 2026-08-05 14:09:00 UTC 
microtar's mtar_write_file_header() and mtar_write_dir_header() functions (src/microtar.c) copy a caller-supplied entry name into the 100-byte `name` field of a stack-allocated mtar_header_t via strcpy(h.name, name), with no check that strlen(name) is less than 100 before the copy. Any application that calls these functions with an externally-influenced filename longer than 99 characters (e.g. when archiving user-supplied or attacker-controlled filenames) triggers a stack buffer overflow.