{"id":"CVE-2026-48103","state":"PUBLISHED","title":"GHSL-2026-119 7-Zip WIM SecurityId OOB read","description":"7-Zip is a file archiver with a high compression ratio. Versions 9.34 through 26.00 contain an off-by-one heap out-of-bounds read in the WIM (Windows Imaging) archive handler's security descriptor lookup. In CHandler::GetSecurity (CPP/7zip/Archive/Wim/WimHandler.cpp), the per-image SecurOffsets table holds numEntries + 1 cumulative offsets, but the check securityId >= SecurOffsets.Size() admits securityId == numEntries, and the function then reads SecurOffsets[securityId + 1], fetching one UInt32 past the end of the heap-allocated CRecordVector (which performs no bounds checking on operator[]). The securityId is attacker-controlled at offset +0xC of any directory entry in WIM metadata, and the handler is registered for .wim, .swm, .esd, and .ppkg and enabled by default in stock 7z.dll; the OOB triggers zero-click in the GUI because 7zFM.exe's ListView calls GetRawProp(kpidNtSecure) for every item during listing (ASan-confirmed), and is also reachable via CLI listing with 7zz l -slt. Impact is limited to denial of service under hardened allocators and minor information disclosure, since the OOB value is only consumed arithmetically as a length and is not surfaced to the attacker; there is no write primitive.","publishedAt":"2026-06-05T15:48:49.891Z","updatedAt":"2026-06-08T16:07:27.768Z","severity":{"score":4.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["mcmilk 7-Zip"],"affected":[{"vendor":"mcmilk","product":"7-Zip","versions":[{"version":">= 9.34, < 26.01","status":"affected"}]}],"references":["https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/"],"weaknesses":["CWE-125"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/48xxx/CVE-2026-48103.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-48103","state":"PUBLISHED","datePublished":"2026-06-05T15:48:49.891Z","dateUpdated":"2026-06-08T16:07:27.768Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-20T18:40:45.835Z"},"containers":{"cna":{"title":"GHSL-2026-119 7-Zip WIM SecurityId OOB read","descriptions":[{"lang":"en","value":"7-Zip is a file archiver with a high compression ratio. Versions 9.34 through 26.00 contain an off-by-one heap out-of-bounds read in the WIM (Windows Imaging) archive handler's security descriptor lookup. In CHandler::GetSecurity (CPP/7zip/Archive/Wim/WimHandler.cpp), the per-image SecurOffsets table holds numEntries + 1 cumulative offsets, but the check securityId >= SecurOffsets.Size() admits securityId == numEntries, and the function then reads SecurOffsets[securityId + 1], fetching one UInt32 past the end of the heap-allocated CRecordVector (which performs no bounds checking on operator[]). The securityId is attacker-controlled at offset +0xC of any directory entry in WIM metadata, and the handler is registered for .wim, .swm, .esd, and .ppkg and enabled by default in stock 7z.dll; the OOB triggers zero-click in the GUI because 7zFM.exe's ListView calls GetRawProp(kpidNtSecure) for every item during listing (ASan-confirmed), and is also reachable via CLI listing with 7zz l -slt. Impact is limited to denial of service under hardened allocators and minor information disclosure, since the OOB value is only consumed arithmetically as a length and is not surfaced to the attacker; there is no write primitive."}],"affected":[{"vendor":"mcmilk","product":"7-Zip","versions":[{"version":">= 9.34, < 26.01","status":"affected"}]}],"references":[{"url":"https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/","name":"https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-125","lang":"en","description":"CWE-125: Out-of-bounds Read","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-05T15:48:49.891Z"},"source":{"advisory":"GHSA-37g2-j8fj-4gf2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-08T16:06:56.976839Z","id":"CVE-2026-48103","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-08T16:07:27.768Z"}}]}}}