CVE catalog
CVE-2026-48104
7-Zip is a file archiver with a high compression ratio. Versions 9.18 through 26.00 contain an uninitialized heap read in the SquashFS archive handler caused by a sparsely populated index array. In th
- Severity
- Medium · CVSS 5.5
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.18% · Oct 25, 2026
7-Zip is a file archiver with a high compression ratio. Versions 9.18 through 26.00 contain an uninitialized heap read in the SquashFS archive handler caused by a sparsely populated index array. In the SquashFS handler, _blockToNode is allocated with capacity for every metadata block but populated only when an inode crosses a block boundary, so a crafted image with few inodes spanning many blocks leaves most slots holding raw heap contents (the underlying allocator does not zero-initialize POD storage). When OpenDir looks up an attacker-influenced blockIndex (derived from the RootInode superblock field), it reads two of these uninitialized slots and passes them as the left/right bounds of a binary search over _nodesPos, which dereferences the midpoint without bounds checking; if the resulting value happens to match the search key, the returned index is used to read a full node struct from _nodes whose fields feed further directory parsing, forming a chained OOB read primitive that is heap-layout-dependent and not reliably triggerable. The SquashFS handler is enabled by default in stock 7z.dll and the issue triggers during Open() with no interaction beyond opening the file; impact is denial of service from wild-pointer dereference and potential heap information disclosure, with no write primitive. Version 26.01 fixes the issue.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | 7zip | sid | 26.05+dfsg-1 | fixed |
| Debian | 7zip | forky | 26.05+dfsg-1 | fixed |
| Debian | 7zip | trixie | 25.01+dfsg-1~deb13u2 | vulnerable |
| Debian | 7zip | bookworm | 22.01+really26.01+dfsg-0+deb12u1 | fixed |
| Debian | 7zip | bookworm-security | 22.01+really26.02+dfsg-0+deb12u1 | fixed |
| Debian | p7zip | trixie | 16.02+transitional.1 | fixed |
| Debian | p7zip | bookworm | 16.02+really26.01+dfsg-0+deb12u1 | fixed |
| Debian | p7zip | bookworm-security | 16.02+really26.02+dfsg-0+deb12u1 | fixed |
| Cpe | 7zip | Not reported | 22.01+really26.01+dfsg-0+deb12u1 | fixed |
| Cpe | 7-zip | Not reported | 26.01 | fixed |
| Alpine | 7zip | 3.24 | 26.01-r0 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | 7zip | source | sid | 26.01+dfsg-1 | unimportant | Not reported | Not reported |
| Debian | 7zip | source | forky | 26.01+dfsg-1 | unimportant | Not reported | Not reported |
| Debian | 7zip | source | trixie | (unfixed) | unimportant | Not reported | Not reported |
| Debian | 7zip | source | bookworm | 22.01+really26.01+dfsg-0+deb12u1 | not yet assigned | Not reported | Not reported |
| Debian | p7zip | source | trixie | 16.02+transitional.1 | unimportant | Not reported | Not reported |
| Debian | p7zip | source | bookworm | 16.02+really26.01+dfsg-0+deb12u1 | not yet assigned | Not reported | Not reported |
| Cpe | 7zip | cpe | Not reported | 22.01+really26.01+dfsg-0+deb12u1 | Not reported | Not reported | Not reported |
| Cpe | 7-zip | cpe | Not reported | 26.01 | Not reported | Not reported | Not reported |
| Alpine | 7zip | apk | 3.24 | 26.01-r0 | Not reported | ALPINE-CVE-2026-48104 | Not reported |
OpenFactory catalog packages
[Debian 13 (Trixie)]
- [7zip]Affected
Details (2)
25.01+dfsg-1~deb13u2· amd64 · trixieAffected
nvd · 7zip · debian · 13
25.01+dfsg-1~deb13u2· arm64 · trixieAffected
nvd · 7zip · debian · 13
- [7zip-standalone]Affected
Source package: [7zip]
Details (2)
25.01+dfsg-1~deb13u2· amd64 · trixieAffected
nvd · 7zip · debian · 13
25.01+dfsg-1~deb13u2· arm64 · trixieAffected
nvd · 7zip · debian · 13
- [p7zip]Fixed
Details (2)
16.02+transitional.1· all · trixieFixed · Fixed:
16.02+transitional.1nvd · p7zip · debian · 13
16.02+transitional.1· all · trixieFixed · Fixed:
16.02+transitional.1nvd · p7zip · debian · 13
- [p7zip-full]Fixed
Source package: [p7zip]
Details (2)
16.02+transitional.1· all · trixieFixed · Fixed:
16.02+transitional.1nvd · p7zip · debian · 13
16.02+transitional.1· all · trixieFixed · Fixed:
16.02+transitional.1nvd · p7zip · debian · 13
[Debian 12 (Bookworm)]
- [7zip]Fixed
Details (6)
22.01+really26.01+dfsg-0+deb12u1· amd64 · bookwormFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
22.01+really26.01+dfsg-0+deb12u1· arm64 · bookwormFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
25.01+dfsg-1~deb13u1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
25.01+dfsg-1~deb13u1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
22.01+really26.02+dfsg-0+deb12u1· amd64 · bookworm-securityFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
22.01+really26.02+dfsg-0+deb12u1· arm64 · bookworm-securityFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
- [7zip-standalone]Fixed
Source package: [7zip]
Details (2)
25.01+dfsg-1~deb13u1~bpo12+1· amd64 · bookworm-backportsFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
25.01+dfsg-1~deb13u1~bpo12+1· arm64 · bookworm-backportsFixed · Fixed:
22.01+really26.01+dfsg-0+deb12u1nvd · 7zip · debian · bookworm; nvd · 7zip · debian · 12
- [p7zip]Fixed
Details (4)
16.02+really26.01+dfsg-0+deb12u1· amd64 · bookwormFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.01+dfsg-0+deb12u1· arm64 · bookwormFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.02+dfsg-0+deb12u1· amd64 · bookworm-securityFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.02+dfsg-0+deb12u1· arm64 · bookworm-securityFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
- [p7zip-full]Fixed
Source package: [p7zip]
Details (4)
16.02+really26.01+dfsg-0+deb12u1· amd64 · bookwormFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.01+dfsg-0+deb12u1· arm64 · bookwormFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.02+dfsg-0+deb12u1· amd64 · bookworm-securityFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
16.02+really26.02+dfsg-0+deb12u1· arm64 · bookworm-securityFixed · Fixed:
16.02+really26.01+dfsg-0+deb12u1nvd · p7zip · debian · bookworm; nvd · p7zip · debian · 12
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2026_22347-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-48104]
- [https://osv.dev/vulnerability/ALPINE-CVE-2026-48104]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-48104]
- [https://security-tracker.debian.org/tracker/CVE-2026-48104]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48104.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-1736.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]