CVE-2026-481037-Zip is a file archiver with a high compression ratio.

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.

CVSS

7.1 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H

Weakness (CWE)

CWE-125

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

Not given

NVD analysis

Analyzed

Record last updated

Jun 17, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.