Vulnerability-Lookup

GHSA-7XVJ-M9X7-QGXQ

Vulnerability from github – Published: 2026-07-24 09:32 – Updated: 2026-07-24 09:32

Details

When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.

This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.

Severity

4.6 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-56391"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-24T09:16:25Z",
    "severity": "MODERATE"
  },
  "details": "GNU coreutils uniq is vulnerable to an out\u2011of\u2011bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. \nThis incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input.\n\nWhen running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure.\n\n\nThis issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.",
  "id": "GHSA-7xvj-m9x7-qgxq",
  "modified": "2026-07-24T09:32:16Z",
  "published": "2026-07-24T09:32:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56391"
    },
    {
      "type": "WEB",
      "url": "https://cert.pl/en/posts/2026/07/CVE-2026-56391"
    },
    {
      "type": "WEB",
      "url": "https://git.savannah.gnu.org/cgit/coreutils.git"
    },
    {
      "type": "WEB",
      "url": "https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=d64e35a8a4c0e4608321433e0d84d917e4e36371"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:L/SC:N/SI:N/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-2026-56391 (GCVE-0-2026-56391)

Vulnerability from cvelistv5 – Published: 2026-07-24 07:44 – Updated: 2026-07-24 12:31 X_Open Source

Title

Out‑of‑bounds Read in GNU coreutils

Summary

GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input. When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure. This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.

Severity

4.6 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-24 12:31 UTC

CWE

CWE-125 - Out-of-bounds Read

Assigner

CERT-PL ENISA root

References

3 references

URL	Tags
https://cert.pl/en/posts/2026/07/CVE-2026-56391	third-party-advisory
https://git.savannah.gnu.org/cgit/coreutils.git/	product
https://git.savannah.gnu.org/cgit/coreutils.git/c…	patch

Impacted products

1 product

Vendor	Product	Version
GNU	coreutils	Affected: 9.5 , ≤ 9.11 (custom)

Credits

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

Show details on NVD website

JSON

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  "containers": {
    "adp": [
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        "metrics": [
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                "id": "CVE-2026-56391",
                "options": [
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                  },
                  {
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-24T12:31:16.655541Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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        {
          "defaultStatus": "unaffected",
          "modules": [
            "uniq"
          ],
          "product": "coreutils",
          "vendor": "GNU",
          "versions": [
            {
              "lessThanOrEqual": "9.11",
              "status": "affected",
              "version": "9.5",
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      ],
      "credits": [
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          "type": "finder",
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    "dateReserved": "2026-06-21T11:40:32.790Z",
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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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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GHSA-7XVJ-M9X7-QGXQ

CVE-2026-56391 (GCVE-0-2026-56391)

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