Vulnerability-Lookup

GHSA-QR96-V34J-WCRQ

Vulnerability from github – Published: 2026-10-01 12:31 – Updated: 2026-10-01 12:31

Details

A flaw was found in tnef. A heap-based buffer overflow can occur in the find_free_number() function when generating numbered backup suffixes for duplicate filenames. When numbered backups are enabled and file overwriting is disabled, an attacker can supply a specially crafted Transport Neutral Encapsulation Format (TNEF) file with an excessive number of colliding attachment filenames, causing the numeric counter to write past the allocated memory buffer. This issue may result in an application crash, leading to a Denial of Service (DoS), or potentially arbitrary code execution.

Severity

3.1 (Low)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L

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{
  "affected": [],
  "aliases": [
    "CVE-2026-103680"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-01T12:17:15Z",
    "severity": "LOW"
  },
  "details": "A flaw was found in tnef. A heap-based buffer overflow can occur in the find_free_number() function when generating numbered backup suffixes for duplicate filenames. When numbered backups are enabled and file overwriting is disabled, an attacker can supply a specially crafted Transport Neutral Encapsulation Format (TNEF) file with an excessive number of colliding attachment filenames, causing the numeric counter to write past the allocated memory buffer. This issue may result in an application crash, leading to a Denial of Service (DoS), or potentially arbitrary code execution.",
  "id": "GHSA-qr96-v34j-wcrq",
  "modified": "2026-10-01T12:31:20Z",
  "published": "2026-10-01T12:31:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-103680"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-103680"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2544478"
    },
    {
      "type": "WEB",
      "url": "https://github.com/verdammelt/tnef"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-103680 (GCVE-0-2026-103680)

Vulnerability from cvelistv5 – Published: 2026-10-01 11:34 – Updated: 2026-10-01 14:58

Title

Tnef: heap buffer overflow in find_free_number() via numbered-backup suffix generation

Summary

Severity

3.1 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-01 14:57 UTC

CWE

CWE-787 - Out-of-bounds Write

Assigner

fedora redhat root Scorecard

References

3 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-103680	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2544478	issue-trackingx_refsource_REDHAT
https://github.com/verdammelt/tnef

Impacted products

1 product

Vendor	Product	Version
		Affected: 0 , ≤ 1.4.18 (semver)

Date Public

2026-10-01 00:00

Credits

Red Hat would like to thank Julien Ahrens (RCE Security GmbH) for reporting this issue.

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JSON

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                "id": "CVE-2026-103680",
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-01T14:57:56.123447Z",
                "version": "2.0.3"
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      "metrics": [
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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.

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.
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GHSA-QR96-V34J-WCRQ

CVE-2026-103680 (GCVE-0-2026-103680)

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