{"id":"ALPINE-CVE-2026-48103","details":"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 \u003e= 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.","modified":"2026-09-14T16:18:08.207277512Z","published":"2026-06-05T17:16:48.133Z","upstream":["CVE-2026-48103"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2026-48103"}],"affected":[{"package":{"name":"7zip","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/7zip?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-48103.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H"}]}