Vulnerability-Lookup

ubuntu-cve-2026-56117

Vulnerability from osv_ubuntu

Published

2026-06-23 17:17

Modified

2026-06-29 11:36

Summary

Details

dhcpcd through 10.3.2, fixed in commit 78ea09e, contains a heap use-after-free vulnerability in the control socket handling within src/control.c that allows local unprivileged attackers to trigger memory corruption when privilege separation is disabled. Attackers can connect to the control socket and send a privileged command such as -x, causing control_recvdata() to free the client object while the same READ+HANGUP event subsequently reaches control_hangup() with the stale pointer, resulting in a use-after-free condition exploitable in deployments using --disable-privsep or where privsep initialization has failed with the control socket operating in mode 0666.

Severity

4.7 (Medium)


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

5.5 (Medium)


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

5.7 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-56117	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-56117	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dhcpcd",
            "binary_version": "1:10.0.6-1ubuntu3.2"
          },
          {
            "binary_name": "dhcpcd-base",
            "binary_version": "1:10.0.6-1ubuntu3.2"
          },
          {
            "binary_name": "dhcpcd5",
            "binary_version": "1:10.0.6-1ubuntu3.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "dhcpcd",
        "purl": "pkg:deb/ubuntu/dhcpcd@1:10.0.6-1ubuntu3.2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:10.0.2-3ubuntu3",
        "1:10.0.5-1",
        "1:10.0.5-2",
        "1:10.0.5-3",
        "1:10.0.5-4",
        "1:10.0.5-5",
        "1:10.0.6-1",
        "1:10.0.6-1ubuntu1",
        "1:10.0.6-1ubuntu2",
        "1:10.0.6-1ubuntu3",
        "1:10.0.6-1ubuntu3.1",
        "1:10.0.6-1ubuntu3.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dhcpcd",
            "binary_version": "1:10.2.4-4"
          },
          {
            "binary_name": "dhcpcd-base",
            "binary_version": "1:10.2.4-4"
          },
          {
            "binary_name": "dhcpcd5",
            "binary_version": "1:10.2.4-4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dhcpcd",
        "purl": "pkg:deb/ubuntu/dhcpcd@1:10.2.4-4?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:10.1.0-8",
        "1:10.1.0-10",
        "1:10.1.0-11",
        "1:10.1.0-12",
        "1:10.2.4-3",
        "1:10.2.4-4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dhcpcd",
            "binary_version": "1:10.3.0-7"
          },
          {
            "binary_name": "dhcpcd-base",
            "binary_version": "1:10.3.0-7"
          },
          {
            "binary_name": "dhcpcd5",
            "binary_version": "1:10.3.0-7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dhcpcd",
        "purl": "pkg:deb/ubuntu/dhcpcd@1:10.3.0-7?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1:10.2.4-4",
        "1:10.3.0-2",
        "1:10.3.0-3",
        "1:10.3.0-7"
      ]
    }
  ],
  "aliases": [],
  "details": "dhcpcd through 10.3.2, fixed in commit 78ea09e, contains a heap use-after-free vulnerability in the control socket handling within src/control.c that allows local unprivileged attackers to trigger memory corruption when privilege separation is disabled. Attackers can connect to the control socket and send a privileged command such as -x, causing control_recvdata() to free the client object while the same READ+HANGUP event subsequently reaches control_hangup() with the stale pointer, resulting in a use-after-free condition exploitable in deployments using --disable-privsep or where privsep initialization has failed with the control socket operating in mode 0666.",
  "id": "UBUNTU-CVE-2026-56117",
  "modified": "2026-06-29T11:36:36Z",
  "published": "2026-06-23T17:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-56117"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-56117"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-56117"
  ]
}

CVE-2026-56117 (GCVE-0-2026-56117)

Vulnerability from cvelistv5 – Published: 2026-06-23 16:14 – Updated: 2026-07-14 21:34 X_Open Source

Title

dhcpcd Heap Use-After-Free via Control Socket Handling

Summary

Severity

5.7 (Medium)


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

4.7 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-416 - Use After Free

Assigner

VulnCheck

References

2 references

URL	Tags
https://github.com/NetworkConfiguration/dhcpcd/co…	patch
https://www.vulncheck.com/advisories/dhcpcd-heap-…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
NetworkConfiguration	dhcpcd	Affected: 0 , ≤ 10.3.2 (semver) Unaffected: 78ea09ed1633a583dbcde6e7bab9df4639ec8a34 (git)

Date Public

2026-06-22 00:00

Credits

CuB3y0nd VulnCheck

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-56117",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-24T13:43:04.591782Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-24T13:43:25.658Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "packageURL": "pkg:github/NetworkConfiguration/dhcpcd",
          "product": "dhcpcd",
          "repo": "https://github.com/NetworkConfiguration/dhcpcd",
          "vendor": "NetworkConfiguration",
          "versions": [
            {
              "lessThanOrEqual": "10.3.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "78ea09ed1633a583dbcde6e7bab9df4639ec8a34",
              "versionType": "git"
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      "credits": [
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        },
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          "value": "VulnCheck"
        }
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      "descriptions": [
        {
          "lang": "en",
          "value": "dhcpcd through 10.3.2, fixed in commit 78ea09e, contains a heap use-after-free vulnerability in the control socket handling within src/control.c that allows local unprivileged attackers to trigger memory corruption when privilege separation is disabled. Attackers can connect to the control socket and send a privileged command such as -x, causing control_recvdata() to free the client object while the same READ+HANGUP event subsequently reaches control_hangup() with the stale pointer, resulting in a use-after-free condition exploitable in deployments using --disable-privsep or where privsep initialization has failed with the control socket operating in mode 0666."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
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          "scenarios": [
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            "availabilityImpact": "HIGH",
            "baseScore": 4.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
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          "scenarios": [
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      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-416",
              "description": "Use After Free",
              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
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          "tags": [
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          "url": "https://github.com/NetworkConfiguration/dhcpcd/commit/78ea09ed1633a583dbcde6e7bab9df4639ec8a34"
        },
        {
          "tags": [
            "third-party-advisory"
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          "url": "https://www.vulncheck.com/advisories/dhcpcd-heap-use-after-free-via-control-socket-handling"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
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      "title": "dhcpcd Heap Use-After-Free via Control Socket Handling",
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  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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    "datePublished": "2026-06-23T16:14:31.918Z",
    "dateReserved": "2026-06-18T19:15:10.651Z",
    "dateUpdated": "2026-07-14T21:34:05.298Z",
    "state": "PUBLISHED"
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  "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.

Action not permitted

ubuntu-cve-2026-56117

Vulnerability from osv_ubuntu

CVE-2026-56117 (GCVE-0-2026-56117)

Tags

Sightings

Nomenclature