Vulnerability-Lookup

GHSA-5PFW-5PV2-2PC6

Vulnerability from github – Published: 2026-09-21 15:32 – Updated: 2026-09-21 15:32

Details

A stack-based buffer overflow flaw was found in fetchmail when built with NTLM support. A malicious or compromised mail server advertising NTLM authentication can send a crafted Type 2 challenge that causes fetchmail to write past a fixed stack buffer while building the NTLM authenticate response. This may lead to remote code execution depending on stack-frame layout, or to authentication failure or process termination under memory hardening.

Severity

8.1 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-94184"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-121"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-21T15:17:38Z",
    "severity": "HIGH"
  },
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  "id": "GHSA-5pfw-5pv2-2pc6",
  "modified": "2026-09-21T15:32:05Z",
  "published": "2026-09-21T15:32:05Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-94184"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-94184"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2537395"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/fetchmail/fetchmail/-/commit/cb5be5c38471eec19e519ace0bc569176317ea92"
    },
    {
      "type": "WEB",
      "url": "https://www.fetchmail.info/fetchmail-SA-2026-01.txt"
    },
    {
      "type": "WEB",
      "url": "https://www.openwall.com/lists/oss-security/2026/06/27/8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-94184 (GCVE-0-2026-94184)

Vulnerability from cvelistv5 – Published: 2026-09-21 14:17 – Updated: 2026-09-21 16:29

Title

Fetchmail: fetchmail: stack-based buffer overflow in ntlm authentication (fetchmail-sa-2026-01)

Summary

Severity

8.1 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-21 14:34 UTC

CWE

CWE-121 - Stack-based Buffer Overflow

Assigner

redhat redhat root

References

5 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-94184	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2537395	issue-trackingx_refsource_REDHAT
https://gitlab.com/fetchmail/fetchmail/-/commit/c…
https://www.fetchmail.info/fetchmail-SA-2026-01.txt
https://www.openwall.com/lists/oss-security/2026/…

Impacted products

5 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-06-27 00:00

Credits

Upstream acknowledges Tristan Madani as the original reporter.

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JSON

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                "id": "CVE-2026-94184",
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                  }
                ],
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        },
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    "cna": {
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          "cpes": [
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          "packageName": "fetchmail",
          "product": "Red Hat Enterprise Linux 10",
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          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "affected",
          "packageName": "fetchmail",
          "product": "Red Hat Enterprise Linux 6",
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      "workarounds": [
        {
          "lang": "en",
          "value": "Rebuild fetchmail without --enable-NTLM (omit NTLM at configure time), or upgrade to fetchmail 6.6.7 or later. Confirm with `fetchmail -V` that the build does not list +NTLM."
        }
      ],
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    "datePublished": "2026-09-21T14:17:16.053Z",
    "dateReserved": "2026-09-21T01:48:54.590Z",
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    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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-5PFW-5PV2-2PC6

CVE-2026-94184 (GCVE-0-2026-94184)

Tags

Sightings

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