Vulnerability-Lookup

UBUNTU-CVE-2025-34451 (CVE-2025-34451)

Vulnerability from osv_ubuntu – Published: 2025-12-18 22:15 – Updated: 2026-05-20 15:17 – Source website

Details

rofl0r/proxychains-ng versions up to and including 4.17 and prior to commit cc005b7 contain a stack-based buffer overflow vulnerability in the function proxy_from_string() located in src/libproxychains.c. When parsing crafted proxy configuration entries containing overly long username or password fields, the application may write beyond the bounds of fixed-size stack buffers, leading to memory corruption or crashes. This vulnerability may allow denial of service and, under certain conditions, could be leveraged for further exploitation depending on the execution environment and applied mitigations.

Severity

6.9 (Medium)


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

7.8 (High)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2025-34451	REPORT
	https://www.cve.org/CVERecord?id=CVE-2025-34451	REPORT
	https://github.com/httpsgithu/proxychains-ng/comm…	REPORT
	https://github.com/marlinkcyber/advisories/blob/m…	REPORT
	https://github.com/rofl0r/proxychains-ng/issues/606	REPORT
	https://www.vulncheck.com/advisories/rofl0r-proxy…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.12-1"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.12-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.12-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.12-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.14-1"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.14-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.14-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.14-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.16-1"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.16-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.16-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.14-3",
        "4.15-1",
        "4.16-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.17-1"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.17-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.17-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.16-3",
        "4.16-4",
        "4.17-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.17-3"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.17-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.17-3?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.17-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libproxychains4",
            "binary_version": "4.17-3build1"
          },
          {
            "binary_name": "proxychains4",
            "binary_version": "4.17-3build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "proxychains-ng",
        "purl": "pkg:deb/ubuntu/proxychains-ng@4.17-3build1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.17-3",
        "4.17-3build1"
      ]
    }
  ],
  "aliases": [],
  "details": "rofl0r/proxychains-ng versions up to and including 4.17 and prior to commit cc005b7 contain a stack-based buffer overflow vulnerability in the function proxy_from_string() located in src/libproxychains.c. When parsing crafted proxy configuration entries containing overly long username or password fields, the application may write beyond the bounds of fixed-size stack buffers, leading to memory corruption or crashes. This vulnerability may allow denial of service and, under certain conditions, could be leveraged for further exploitation depending on the execution environment and applied mitigations.",
  "id": "UBUNTU-CVE-2025-34451",
  "modified": "2026-05-20T15:17:33Z",
  "published": "2025-12-18T22:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2025-34451"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-34451"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/httpsgithu/proxychains-ng/commit/cc005b7"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/marlinkcyber/advisories/blob/main/advisories/MCSAID-2025-008-proxychains-ng-stack-buffer-overflow-proxy_from_string.md"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/rofl0r/proxychains-ng/issues/606"
    },
    {
      "type": "REPORT",
      "url": "https://www.vulncheck.com/advisories/rofl0r-proxychains-ng-stack-based-buffer-overflow"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2025-34451"
  ]
}

CVE-2025-34451 (GCVE-0-2025-34451)

Vulnerability from cvelistv5 – Published: 2025-12-18 21:16 – Updated: 2026-05-14 02:08

Title

rofl0r/proxychains-ng <= 4.17 Stack-based Buffer Overflow

Summary

Severity

6.9 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-12-18 21:37 UTC

CWE

CWE-121 - Stack-based Buffer Overflow

Assigner

VulnCheck mitre root

References

4 references

URL	Tags
https://github.com/marlinkcyber/advisories/blob/m…	technical-descriptionexploit
https://github.com/rofl0r/proxychains-ng/issues/606	issue-tracking
https://github.com/httpsgithu/proxychains-ng/comm…	patch
https://www.vulncheck.com/advisories/rofl0r-proxy…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
rofl0r	proxychains-ng	Affected: 0 , ≤ 4.17 (custom) Unaffected: cc005b7132811c9149e77b5e33cff359fc95512e (git) cpe:2.3:a:proxychains-ng_project:proxychains-ng::::::::

Credits

Vlatko Kosturjak with Marlink Cyber

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-34451",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-12-18T21:37:50.277828Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-12-18T21:38:07.266Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/marlinkcyber/advisories/blob/main/advisories/MCSAID-2025-008-proxychains-ng-stack-buffer-overflow-proxy_from_string.md"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageName": "proxychains-ng",
          "packageURL": "pkg:github/rofl0r/proxychains-ng",
          "product": "proxychains-ng",
          "repo": "https://github.com/rofl0r/proxychains-ng",
          "vendor": "rofl0r",
          "versions": [
            {
              "lessThanOrEqual": "4.17",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            },
            {
              "status": "unaffected",
              "version": "cc005b7132811c9149e77b5e33cff359fc95512e",
              "versionType": "git"
            }
          ]
        }
      ],
      "cpeApplicability": [
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          "nodes": [
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              "cpeMatch": [
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      "metrics": [
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          "cvssV4_0": {
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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.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.