{"id":"CVE-2026-42512","state":"PUBLISHED","title":"Remotely triggerable out-of-bounds heap write in dhclient","description":"As dhclient is building an environment to pass to dhclient-script, it may need to resize the array of string pointers.  The code which expands the array incorrectly calculates its new size when requesting memory, resulting in a heap buffer overrun.\n\nA specially crafted packet can cause dhclient to overrun its buffer of environment entries.  This can result in a crash, but it may be possible to leverage this bug to achieve remote code execution.","publishedAt":"2026-04-30T07:58:37.145Z","updatedAt":"2026-05-01T15:26:06.292Z","severity":{"score":8.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"CISA-ADP"},"assigner":"freebsd","products":["FreeBSD FreeBSD"],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.0-RELEASE","status":"affected","lessThan":"p7","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p3","versionType":"release"},{"version":"14.3-RELEASE","status":"affected","lessThan":"p12","versionType":"release"},{"version":"13.5-RELEASE","status":"affected","lessThan":"p13","versionType":"release"}],"modules":["dhclient"]}],"references":["https://security.freebsd.org/advisories/FreeBSD-SA-26:15.dhclient.asc"],"weaknesses":["CWE-122"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42512.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42512","state":"PUBLISHED","datePublished":"2026-04-30T07:58:37.145Z","dateUpdated":"2026-05-01T15:26:06.292Z","assignerShortName":"freebsd","assignerOrgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateReserved":"2026-04-28T05:31:44.956Z"},"containers":{"cna":{"title":"Remotely triggerable out-of-bounds heap write in dhclient","descriptions":[{"lang":"en","value":"As dhclient is building an environment to pass to dhclient-script, it may need to resize the array of string pointers.  The code which expands the array incorrectly calculates its new size when requesting memory, resulting in a heap buffer overrun.\n\nA specially crafted packet can cause dhclient to overrun its buffer of environment entries.  This can result in a crash, but it may be possible to leverage this bug to achieve remote code execution."}],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.0-RELEASE","status":"affected","lessThan":"p7","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p3","versionType":"release"},{"version":"14.3-RELEASE","status":"affected","lessThan":"p12","versionType":"release"},{"version":"13.5-RELEASE","status":"affected","lessThan":"p13","versionType":"release"}],"modules":["dhclient"]}],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:15.dhclient.asc","tags":["vendor-advisory"]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-122","description":"CWE-122: Heap-based Buffer Overflow","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"freebsd","orgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateUpdated":"2026-04-30T07:58:37.145Z"},"datePublic":"2026-04-29T19:00:00.000Z","credits":[{"lang":"en","type":"finder","value":"Joshua Rogers of AISLE Research Team"}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":8.1,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"HIGH","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-05-01T03:55:53.107126Z","id":"CVE-2026-42512","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-01T15:26:06.292Z"}}]}}}