DEBIAN-CVE-2026-48095
7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 << (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog >= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching "NTFS " at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.
DEBIAN-CVE-2026-48095
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-48095
7zip
Source reference: /affected/0/package/name
- Affected versions
- 22.01+dfsg-10~exp1
Source reference:
/affected/0/versions22.01+dfsg-8Source reference:
/affected/0/versions22.01+dfsg-8+deb12u1Source reference:
/affected/0/versions22.01+dfsg-9Source reference:
/affected/0/versions22.01+really25.01+dfsg-0+deb12u1Source reference:
/affected/0/versions - Fixed versions
- 22.01+really26.01+dfsg-0+deb12u1
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
7zip
Source reference: /affected/1/package/name
- Affected versions
- 24.09+dfsg-8
Source reference:
/affected/1/versions25.00+dfsg-1Source reference:
/affected/1/versions25.01+dfsg-1Source reference:
/affected/1/versions25.01+dfsg-1~deb13u1Source reference:
/affected/1/versions25.01+dfsg-1~deb13u1~bpo12+1Source reference:
/affected/1/versions25.01+dfsg-1~deb13u2Source reference:
/affected/1/versions25.01+dfsg-2Source reference:
/affected/1/versions25.01+dfsg-3Source reference:
/affected/1/versions25.01+dfsg-4Source reference:
/affected/1/versions25.01+dfsg-5Source reference:
/affected/1/versions26.00+dfsg-1Source reference:
/affected/1/versions26.00+dfsg-2Source reference:
/affected/1/versions26.00+dfsg-3Source reference:
/affected/1/versions26.00+dfsg-4Source reference:
/affected/1/versions26.00+dfsg-5Source reference:
/affected/1/versions26.00+dfsg1-1Source reference:
/affected/1/versions26.00+dfsg1-2Source reference:
/affected/1/versions26.00+dfsg1-3Source reference:
/affected/1/versions26.01+dfsg-1Source reference:
/affected/1/versions26.01+dfsg-2Source reference:
/affected/1/versions26.01+dfsg-3Source reference:
/affected/1/versions26.02+dfsg-1Source reference:
/affected/1/versions26.02+dfsg-2Source reference:
/affected/1/versions26.02+dfsg-3Source reference:
/affected/1/versions26.03+dfsg-1Source reference:
/affected/1/versions26.03+dfsg-2Source reference:
/affected/1/versions26.03+dfsg-3Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
7zip
Source reference: /affected/2/package/name
- Affected versions
- 24.09+dfsg-8
Source reference:
/affected/2/versions25.00+dfsg-1Source reference:
/affected/2/versions25.01+dfsg-1Source reference:
/affected/2/versions25.01+dfsg-1~deb13u1Source reference:
/affected/2/versions25.01+dfsg-1~deb13u1~bpo12+1Source reference:
/affected/2/versions25.01+dfsg-1~deb13u2Source reference:
/affected/2/versions25.01+dfsg-2Source reference:
/affected/2/versions25.01+dfsg-3Source reference:
/affected/2/versions25.01+dfsg-4Source reference:
/affected/2/versions25.01+dfsg-5Source reference:
/affected/2/versions26.00+dfsg-1Source reference:
/affected/2/versions26.00+dfsg-2Source reference:
/affected/2/versions26.00+dfsg-3Source reference:
/affected/2/versions26.00+dfsg-4Source reference:
/affected/2/versions26.00+dfsg-5Source reference:
/affected/2/versions26.00+dfsg1-1Source reference:
/affected/2/versions26.00+dfsg1-2Source reference:
/affected/2/versions26.00+dfsg1-3Source reference:
/affected/2/versions - Fixed versions
- 26.01+dfsg-1
Source reference:
/affected/2/ranges - Prerequisites
- Not stated in this record
p7zip
Source reference: /affected/3/package/name
- Affected versions
- 16.02+dfsg-8
Source reference:
/affected/3/versions16.02+really25.01+dfsg-0+deb12u1Source reference:
/affected/3/versions - Fixed versions
- 16.02+really26.01+dfsg-0+deb12u1
Source reference:
/affected/3/ranges - Prerequisites
- Not stated in this record
p7zip
Source reference: /affected/4/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 16.02+transitional.1
Source reference:
/affected/4/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "22.01+really26.01+dfsg-0+deb12u1"
}
]
}
],
"package": {
"name": "7zip",
"purl": "pkg:deb/debian/7zip?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"22.01+dfsg-10~exp1",
"22.01+dfsg-8",
"22.01+dfsg-8+deb12u1",
"22.01+dfsg-9",
"22.01+really25.01+dfsg-0+deb12u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48095.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "7zip",
"purl": "pkg:deb/debian/7zip?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"24.09+dfsg-8",
"25.00+dfsg-1",
"25.01+dfsg-1",
"25.01+dfsg-1~deb13u1",
"25.01+dfsg-1~deb13u1~bpo12+1",
"25.01+dfsg-1~deb13u2",
"25.01+dfsg-2",
"25.01+dfsg-3",
"25.01+dfsg-4",
"25.01+dfsg-5",
"26.00+dfsg-1",
"26.00+dfsg-2",
"26.00+dfsg-3",
"26.00+dfsg-4",
"26.00+dfsg-5",
"26.00+dfsg1-1",
"26.00+dfsg1-2",
"26.00+dfsg1-3",
"26.01+dfsg-1",
"26.01+dfsg-2",
"26.01+dfsg-3",
"26.02+dfsg-1",
"26.02+dfsg-2",
"26.02+dfsg-3",
"26.03+dfsg-1",
"26.03+dfsg-2",
"26.03+dfsg-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48095.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "26.01+dfsg-1"
}
]
}
],
"package": {
"name": "7zip",
"purl": "pkg:deb/debian/7zip?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"24.09+dfsg-8",
"25.00+dfsg-1",
"25.01+dfsg-1",
"25.01+dfsg-1~deb13u1",
"25.01+dfsg-1~deb13u1~bpo12+1",
"25.01+dfsg-1~deb13u2",
"25.01+dfsg-2",
"25.01+dfsg-3",
"25.01+dfsg-4",
"25.01+dfsg-5",
"26.00+dfsg-1",
"26.00+dfsg-2",
"26.00+dfsg-3",
"26.00+dfsg-4",
"26.00+dfsg-5",
"26.00+dfsg1-1",
"26.00+dfsg1-2",
"26.00+dfsg1-3"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48095.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "16.02+really26.01+dfsg-0+deb12u1"
}
]
}
],
"package": {
"name": "p7zip",
"purl": "pkg:deb/debian/p7zip?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"16.02+dfsg-8",
"16.02+really25.01+dfsg-0+deb12u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48095.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "16.02+transitional.1"
}
]
}
],
"package": {
"name": "p7zip",
"purl": "pkg:deb/debian/p7zip?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48095.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #57170 · Revision 1
- Added to Heist Feed
- Publisher date