Vulnerability-Lookup

GHSA-RC3P-P5W3-FM9J

Vulnerability from github – Published: 2026-08-10 12:31 – Updated: 2026-08-10 12:31

Details

GNU cpio contains a Path Traversal vulnerability in its tar archive extraction functionality. When extracting a tar archive in copy-in mode with the --no-absolute-filenames option, the extracted file name is normalized but the tar hard-link target is passed to the link_to_name function without equivalent sanitization before calling link function. A tar archive provided by an attacker, containing a hard-link entry whose linkname is set to an absolute path outside the extraction directory, can cause cpio to create a hard link to an existing file outside the intended extraction directory, breaking the expected guarantee of --no-absolute-filenames and allowing archive-controlled linkage to external files.

This issue has been fixed in commit e2b9cbdd3354d2b1569b7390d1bc15c1930559ad

Severity

4.6 (Medium)


                  
                    CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

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  "affected": [],
  "aliases": [
    "CVE-2026-66484"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22"
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    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T11:17:27Z",
    "severity": "MODERATE"
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  "details": "GNU cpio contains a Path Traversal vulnerability in its tar archive extraction functionality. When extracting a tar archive in copy-in mode with the --no-absolute-filenames option, the extracted file name is normalized but the tar hard-link target is passed to the link_to_name function without equivalent sanitization before calling link function. A tar archive provided by an attacker, containing a hard-link entry whose linkname is set to an absolute path outside the extraction directory, can cause cpio to create a hard link to an existing file outside the intended extraction directory, breaking the expected guarantee of --no-absolute-filenames and allowing archive-controlled linkage to external files.\n\nThis issue has been fixed in commit e2b9cbdd3354d2b1569b7390d1bc15c1930559ad",
  "id": "GHSA-rc3p-p5w3-fm9j",
  "modified": "2026-08-10T12:31:51Z",
  "published": "2026-08-10T12:31:50Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66484"
    },
    {
      "type": "WEB",
      "url": "https://cert.pl/en/posts/2026/08/CVE-2026-66484"
    },
    {
      "type": "WEB",
      "url": "https://git.savannah.gnu.org/cgit/cpio.git"
    }
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  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-66484 (GCVE-0-2026-66484)

Vulnerability from cvelistv5 – Published: 2026-08-10 10:25 – Updated: 2026-08-10 10:57 X_Open Source

Title

Path Traversal in GNU cpio

Summary

Severity

4.6 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Assigner

CERT-PL

References

2 references

URL	Tags
https://cert.pl/en/posts/2026/08/CVE-2026-66484	third-party-advisory
https://git.savannah.gnu.org/cgit/cpio.git	product

Impacted products

1 product

Vendor	Product	Version
GNU	cpio	Affected: 0 , ≤ 2.15 (custom)

Credits

Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-RC3P-P5W3-FM9J

CVE-2026-66484 (GCVE-0-2026-66484)

Tags

Sightings

Nomenclature