CVE-2026-48103
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Mitigation details
CVE-2026-48103 NameCVE-2026-48103 SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) Vulnerable and fixed packages The table below lists information on source packages. Source PackageReleaseVersionStatus 7zip (PTS)bookworm22.01+really25.01+dfsg-0+deb12u1vulnerable…
CVE-2026-48103
| Name | CVE-2026-48103 |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| 7zip (PTS) | bookworm | 22.01+really25.01+dfsg-0+deb12u1 | vulnerable |
| trixie | 25.01+dfsg-1~deb13u2 | vulnerable | |
| forky, sid | 26.01+dfsg-2 | fixed | |
| p7zip (PTS) | bullseye | 16.02+dfsg-8 | vulnerable |
| bullseye (security) | 16.02+really25.01+dfsg-0+deb11u1 | vulnerable | |
| bookworm | 16.02+really25.01+dfsg-0+deb12u1 | vulnerable | |
| trixie | 16.02+transitional.1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| 7zip | source | (unstable) | 26.01+dfsg-1 | |||
| p7zip | source | (unstable) | 16.02+transitional.1 |
Notes
Since p7zip/16.02+transitional.1 src:p7zip is only a empty source package
depending on 7zip. Mark this version as fixed version.
https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/
Apply commands
Since p7zip/16.02+transitional.1 src:p7zip is only a empty source packagedepending on 7zip. Mark this version as fixed version.https://securitylab.github.com/advisories/GHSL-2026-115_GHSL-2026-122_7-zip/OS impact
Debian Mixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 16.02+transitional.1 |
| sid | Fixed | 26.01+dfsg-1 |
| forky | Fixed | 26.01+dfsg-1 |
| bullseye | Affected | — |
| bookworm | Affected | — |
References
CWEs
CWE-125
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.