RHSA-2026:79717

Vulnerability from csaf_redhat - Published: 2026-10-08 23:29 - Updated: 2026-10-09 01:28
Summary
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
Severity
Moderate
Notes
Topic: An update for Red Hat Hardened Images RPMs is now available.
Details: This update includes the following RPMs: gzip: * gzip-1.15-1.hum1 (aarch64, x86_64) * gzip-1.15-1.hum1.src (src) Security Fix(es): gzip: * CVE-2026-41991 * CVE-2026-41992
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2026-41991

A flaw was found in the `gzexe` utility of GNU `gzip`. When the `mktemp` utility is not available, `gzexe` creates temporary files with predictable names based on the process ID. A local attacker can exploit this by pre-creating a symbolic link to an arbitrary file at the predicted temporary file path. This can lead to a Time-of-Check to Time-of-Use (TOCTOU) condition, allowing the attacker to overwrite arbitrary files on the system.

6.0 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:H
CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Affected products
Product Identifier Version Remediation
Unresolved product id: Red Hat Hardened Images:gzip-0:1.15-1.hum1@aarch64 —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:gzip-0:1.15-1.hum1@src —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:gzip-0:1.15-1.hum1@x86_64 —
Vendor Fix fix
Workaround
Threats
Impact Moderate
CVE-2026-41992

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.

3.6 (Low)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L
CWE-125 - Out-of-bounds Read
Affected products
Fixed 3 products, the same list as for CVE-2026-41991
Threats
Impact Low
References
To clipboard 

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        "id": "CWE-59",
        "name": "Improper Link Resolution Before File Access (\u0027Link Following\u0027)"
      },
      "discovery_date": "2026-06-29T12:01:03.862009+00:00",
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          "text": "A flaw was found in the `gzexe` utility of GNU `gzip`. When the `mktemp` utility is not available, `gzexe` creates temporary files with predictable names based on the process ID. A local attacker can exploit this by pre-creating a symbolic link to an arbitrary file at the predicted temporary file path. This can lead to a Time-of-Check to Time-of-Use (TOCTOU) condition, allowing the attacker to overwrite arbitrary files on the system.",
          "title": "Vulnerability description"
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          "text": "A flaw was found in the gzexe utility of GNU gzip. When the mktemp utility is not available in the user\u0027s PATH, gzexe creates temporary files with predictable names based on the process ID. A local attacker can exploit this by creating a symbolic link at the predicted temporary file path, leading to a TOCTOU race condition that allows arbitrary file overwrite. On Red Hat Enterprise Linux, mktemp is provided by coreutils which is always installed, making the vulnerable fallback code path effectively unreachable in standard deployments.",
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            "confidentialityImpact": "NONE",
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            "Red Hat Hardened Images:gzip-0:1.15-1.hum1@x86_64"
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      ],
      "title": "gzip: gzip: Arbitrary file overwrite via insecure temporary file handling in gzexe utility"
    },
    {
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          "title": "Vulnerability description"
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            "attackVector": "LOCAL",
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            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:L",
            "version": "3.1"
          },
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            "Red Hat Hardened Images:gzip-0:1.15-1.hum1@src",
            "Red Hat Hardened Images:gzip-0:1.15-1.hum1@x86_64"
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        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Low"
        }
      ],
      "title": "gzip: gzip: Information disclosure via global buffer overflow in LZH decompression"
    }
  ]
}



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