{"api_version":"1","generated_at":"2026-06-24T05:51:03+00:00","cve":"CVE-2026-56114","urls":{"html":"https://cve.report/CVE-2026-56114","api":"https://cve.report/api/cve/CVE-2026-56114.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-56114","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-56114"},"summary":{"title":"dhcpcd Stack Out-of-Bounds Write in dhcp6_makemessage()","description":"dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.","state":"PUBLISHED","assigner":"VulnCheck","published_at":"2026-06-23 17:17:09","updated_at":"2026-06-23 17:57:05"},"problem_types":["CWE-787","CWE-787 Out-of-bounds Write"],"metrics":[{"version":"4.0","source":"disclosure@vulncheck.com","type":"Secondary","score":"6","severity":"MEDIUM","vector":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","data":{"version":"4.0","vectorString":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":6,"baseSeverity":"MEDIUM","attackVector":"ADJACENT","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}},{"version":"4.0","source":"CNA","type":"CVSS","score":"6","severity":"MEDIUM","vector":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","data":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"ADJACENT","baseScore":6,"baseSeverity":"MEDIUM","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/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"}},{"version":"3.1","source":"disclosure@vulncheck.com","type":"Primary","score":"5.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.3,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"CVSS","score":"5.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"HIGH","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://github.com/NetworkConfiguration/dhcpcd/commit/2f00c7bfc408b6582d331932dfa47829c4819029","name":"https://github.com/NetworkConfiguration/dhcpcd/commit/2f00c7bfc408b6582d331932dfa47829c4819029","refsource":"disclosure@vulncheck.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.vulncheck.com/advisories/dhcpcd-stack-out-of-bounds-write-in-dhcp6-makemessage","name":"https://www.vulncheck.com/advisories/dhcpcd-stack-out-of-bounds-write-in-dhcp6-makemessage","refsource":"disclosure@vulncheck.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-56114","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56114","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"NetworkConfiguration","product":"dhcpcd","version":"affected 10.3.2 semver","platforms":[]},{"source":"CNA","vendor":"NetworkConfiguration","product":"dhcpcd","version":"unaffected 2f00c7bfc408b6582d331932dfa47829c4819029 git","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"CuB3y0nd","lang":"en"},{"source":"CNA","value":"VulnCheck","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"affected","product":"dhcpcd","repo":"https://github.com/NetworkConfiguration/dhcpcd","vendor":"NetworkConfiguration","versions":[{"lessThanOrEqual":"10.3.2","status":"affected","version":"0","versionType":"semver"},{"status":"unaffected","version":"2f00c7bfc408b6582d331932dfa47829c4819029","versionType":"git"}]}],"credits":[{"lang":"en","type":"finder","value":"CuB3y0nd"},{"lang":"en","type":"finder","value":"VulnCheck"}],"datePublic":"2026-06-22T00:00:00.000Z","descriptions":[{"lang":"en","value":"dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory."}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"ADJACENT","baseScore":6,"baseSeverity":"MEDIUM","exploitMaturity":"NOT_DEFINED","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/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"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-787","description":"Out-of-bounds Write","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-06-23T16:16:28.614Z","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","shortName":"VulnCheck"},"references":[{"tags":["patch"],"url":"https://github.com/NetworkConfiguration/dhcpcd/commit/2f00c7bfc408b6582d331932dfa47829c4819029"},{"tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/dhcpcd-stack-out-of-bounds-write-in-dhcp6-makemessage"}],"source":{"discovery":"UNKNOWN"},"tags":["x_open-source"],"title":"dhcpcd Stack Out-of-Bounds Write in dhcp6_makemessage()","x_generator":{"engine":"vulncheck"}}},"cveMetadata":{"assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","assignerShortName":"VulnCheck","cveId":"CVE-2026-56114","datePublished":"2026-06-23T16:08:10.043Z","dateReserved":"2026-06-18T19:15:10.650Z","dateUpdated":"2026-06-23T16:16:28.614Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-23 17:17:09","lastModifiedDate":"2026-06-23 17:57:05","problem_types":["CWE-787","CWE-787 Out-of-bounds Write"],"metrics":{"cvssMetricV40":[{"source":"disclosure@vulncheck.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":6,"baseSeverity":"MEDIUM","attackVector":"ADJACENT","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"disclosure@vulncheck.com","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.3,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.6,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"56114","Ordinal":"1","Title":"dhcpcd Stack Out-of-Bounds Write in dhcp6_makemessage()","CVE":"CVE-2026-56114","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"56114","Ordinal":"1","NoteData":"dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.","Type":"Description","Title":"dhcpcd Stack Out-of-Bounds Write in dhcp6_makemessage()"}]}}}