Bug 2494159 (CVE-2026-41992)

Summary: CVE-2026-41992 gzip: gzip: Information disclosure via global buffer overflow in LZH decompression
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, gtanzill, jbuscemi, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sdawley, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in GNU gzip. This global buffer overflow vulnerability in the LZH decompression logic is caused by improper reuse of shared global state between different decompression formats. An attacker can exploit this by providing a specially crafted LZW file followed by a specially crafted LZH file to the `gzip -d` command. This can lead to an out-of-bounds read, potentially resulting in information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-29 12:01:35 UTC 
GNU gzip contains a global buffer overflow vulnerability in the LZH decompression logic caused by improper reuse of shared global state between different decompression formats within a single execution. GNU gzip maintains a global array that is shared across the LZ77, LZW, and LZH decompression routines and is not reinitialized between files processed in the same invocation.
By decompressing a specially crafted LZW file followed by a specially crafted LZH file in a single gzip -d command, an attacker can poison the shared global state and subsequently trigger an out‑of‑bounds read in the LZH decoder. The LZH decompression logic follows stale values left in the shared array, causing reads past the end of the allocated global buffer.

This issue has been fixed in the commit 63dbf6b3b9e6e781df1a6a64e609b10e23969681
Comment 3 errata-xmlrpc 2026-08-31 15:28:49 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:61625 https://access.redhat.com/errata/RHSA-2026:61625
Comment 4 errata-xmlrpc 2026-08-31 15:44:30 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:61623 https://access.redhat.com/errata/RHSA-2026:61623