RHSA-2026:50807

Vulnerability from csaf_redhat - Published: 2026-08-05 12:24 - Updated: 2026-09-22 21:30
Summary
Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update
Severity
Moderate
Notes
Topic: An update for Red Hat Hardened Images RPMs is now available.
Details: This update includes the following RPMs: tar: * tar-1.35-9.2.hum1 (aarch64, x86_64) * tar-1.35-9.2.hum1.src (src)
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-2026-18508

A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not confined to the designated top-level directory and may resolve relative to the extraction working directory. A crafted archive can create hardlinks that escape the intended boundary and, when combined with a preexisting symbolic link under the working directory, may allow writing outside that boundary during a single extraction.

4.4 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Affected products
Product Identifier Version Remediation
Unresolved product id: Red Hat Hardened Images:tar-0:1.35-9.2.hum1@aarch64 —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:tar-0:1.35-9.2.hum1@src —
Vendor Fix fix
Workaround
Unresolved product id: Red Hat Hardened Images:tar-0:1.35-9.2.hum1@x86_64 —
Vendor Fix fix
Workaround
Threats
Impact Moderate
References
Acknowledgments
Red Hat Pavel Cahyna
To clipboard 

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        "text": "This update includes the following RPMs:\n\ntar:\n  * tar-1.35-9.2.hum1 (aarch64, x86_64)\n  * tar-1.35-9.2.hum1.src (src)",
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      "acknowledgments": [
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          "names": [
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          "organization": "Red Hat",
          "summary": "This issue was discovered by Red Hat."
        }
      ],
      "cve": "CVE-2026-18508",
      "cwe": {
        "id": "CWE-59",
        "name": "Improper Link Resolution Before File Access (\u0027Link Following\u0027)"
      },
      "discovery_date": "2026-07-31T16:57:51.102000+00:00",
      "ids": [
        {
          "system_name": "Red Hat Bugzilla ID",
          "text": "2509843"
        }
      ],
      "notes": [
        {
          "category": "description",
          "text": "A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not confined to the designated top-level directory and may resolve relative to the extraction working directory. A crafted archive can create hardlinks that escape the intended boundary and, when combined with a preexisting symbolic link under the working directory, may allow writing outside that boundary during a single extraction.",
          "title": "Vulnerability description"
        },
        {
          "category": "summary",
          "text": "tar: tar: --one-top-level hardlink targets not confined to top-level directory enabling arbitrary file overwrite",
          "title": "Vulnerability summary"
        },
        {
          "category": "other",
          "text": "Red Hat Enterprise Linux is affected. This issue only applies when the --one-top-level option is used to extract an untrusted archive. Default tar extraction without --one-top-level is not impacted by this specific boundary failure. Users should avoid using --one-top-level as the sole confinement mechanism for untrusted archives until fixed packages are available.",
          "title": "Statement"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product\u0027s status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
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          "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@src",
          "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@x86_64"
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          "url": "https://access.redhat.com/security/cve/CVE-2026-18508"
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          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2509843"
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        },
        {
          "category": "external",
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          "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-18508"
        }
      ],
      "release_date": "2026-07-31T00:00:00+00:00",
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-08-05T12:24:25+00:00",
          "details": "For details on how to apply this update, which includes the changes described in this advisory, refer to:\nhttps://images.redhat.com/",
          "product_ids": [
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@aarch64",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@src",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@x86_64"
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            "category": "none"
          },
          "url": "https://access.redhat.com/errata/RHSA-2026:50807"
        },
        {
          "category": "workaround",
          "details": "Do not use --one-top-level as the sole confinement mechanism when extracting untrusted archives. Prefer extracting as an unprivileged user into a freshly created empty directory after changing into that directory (mkdir and cd), avoid extracting as root from sensitive working directories such as /, and follow the GNU tar security guidance for untrusted archives.",
          "product_ids": [
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@aarch64",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@src",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@x86_64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "NONE",
            "baseScore": 4.4,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "products": [
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@aarch64",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@src",
            "Red Hat Hardened Images:tar-0:1.35-9.2.hum1@x86_64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Moderate"
        }
      ],
      "title": "tar: tar: --one-top-level hardlink targets not confined to top-level directory enabling arbitrary file overwrite"
    }
  ]
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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