DEBIAN-CVE-2026-23879
py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Versions 1.1.2 and below contain an an arbitrary file write vulnerability, which allows symbolic links to be recreated outside the destination directory via crafted malicious symbolic link chains. When using extractall to extract an archive, the library restores these symbolic links, linking them to arbitrary directories on the host file system. During extraction, the program only checks the link arcname within the destination directory, but ignores the combined symlink path resolution. Attackers can exploit this vulnerability by constructing malicious archives, thereby bypassing the directory boundary restrictions implemented by the extractor. Subsequent extraction of regular files through these symbolic links can result in arbitrary file writes. This vulnerability may lead to remote code execution, privilege escalation, data corruption, or denial of service. This issue has been fixed in version 1.1.3.
DEBIAN-CVE-2026-23879
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-2026-23879
py7zr
Source reference: /affected/0/package/name
- Affected versions
- 0.11.3+dfsg-5
Source reference:
/affected/0/versions0.11.3+dfsg-6Source reference:
/affected/0/versions0.11.3+dfsg-7Source reference:
/affected/0/versions0.11.3+dfsg-8Source reference:
/affected/0/versions0.21.0+dfsg-1Source reference:
/affected/0/versions0.21.0+dfsg-2Source reference:
/affected/0/versions0.21.1+dfsg-1Source reference:
/affected/0/versions0.22.0+dfsg-1Source reference:
/affected/0/versions1.0.0+dfsg1-1Source reference:
/affected/0/versions1.0.0+dfsg1-2Source reference:
/affected/0/versions1.0.0+dfsg1-3Source reference:
/affected/0/versions1.0.0+dfsg1-3~bpo13+1Source reference:
/affected/0/versions1.0.0+dfsg1-4Source reference:
/affected/0/versions1.0.0+dfsg1-5Source reference:
/affected/0/versions1.1.0+dfsg-1~exp1Source reference:
/affected/0/versions1.1.2+dfsg-1Source reference:
/affected/0/versions1.1.2+dfsg-1~exp1Source reference:
/affected/0/versions1.1.2+dfsg-2Source reference:
/affected/0/versions1.1.2+really1.1.0+dfsg-1Source reference:
/affected/0/versions1.1.2-1+really1.1.0+dfsg-1Source reference:
/affected/0/versions1.1.2-1+really1.1.0+dfsg-2Source reference:
/affected/0/versions1.1.3+dfsg-1Source reference:
/affected/0/versions1.1.3+dfsg-2Source reference:
/affected/0/versions1.1.3+dfsg-3Source reference:
/affected/0/versions1.1.3+dfsg-4Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
py7zr
Source reference: /affected/1/package/name
- Affected versions
- 0.22.0+dfsg-1
Source reference:
/affected/1/versions1.0.0+dfsg1-1Source reference:
/affected/1/versions1.0.0+dfsg1-2Source reference:
/affected/1/versions1.0.0+dfsg1-3Source reference:
/affected/1/versions1.0.0+dfsg1-3~bpo13+1Source reference:
/affected/1/versions1.0.0+dfsg1-4Source reference:
/affected/1/versions1.0.0+dfsg1-5Source reference:
/affected/1/versions1.1.0+dfsg-1~exp1Source reference:
/affected/1/versions1.1.2+dfsg-1Source reference:
/affected/1/versions1.1.2+dfsg-1~exp1Source reference:
/affected/1/versions1.1.2+dfsg-2Source reference:
/affected/1/versions1.1.2+really1.1.0+dfsg-1Source reference:
/affected/1/versions1.1.2-1+really1.1.0+dfsg-1Source reference:
/affected/1/versions1.1.2-1+really1.1.0+dfsg-2Source reference:
/affected/1/versions1.1.3+dfsg-1Source reference:
/affected/1/versions1.1.3+dfsg-2Source reference:
/affected/1/versions1.1.3+dfsg-3Source reference:
/affected/1/versions1.1.3+dfsg-4Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
py7zr
Source reference: /affected/2/package/name
- Affected versions
- 0.22.0+dfsg-1
Source reference:
/affected/2/versions1.0.0+dfsg1-1Source reference:
/affected/2/versions1.0.0+dfsg1-2Source reference:
/affected/2/versions1.0.0+dfsg1-3Source reference:
/affected/2/versions1.0.0+dfsg1-3~bpo13+1Source reference:
/affected/2/versions1.0.0+dfsg1-4Source reference:
/affected/2/versions1.0.0+dfsg1-5Source reference:
/affected/2/versions1.1.0+dfsg-1~exp1Source reference:
/affected/2/versions1.1.2+dfsg-1~exp1Source reference:
/affected/2/versions - Fixed versions
- 1.1.2+dfsg-1
Source reference:
/affected/2/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"
}
]
}
],
"package": {
"name": "py7zr",
"purl": "pkg:deb/debian/py7zr?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"0.11.3+dfsg-5",
"0.11.3+dfsg-6",
"0.11.3+dfsg-7",
"0.11.3+dfsg-8",
"0.21.0+dfsg-1",
"0.21.0+dfsg-2",
"0.21.1+dfsg-1",
"0.22.0+dfsg-1",
"1.0.0+dfsg1-1",
"1.0.0+dfsg1-2",
"1.0.0+dfsg1-3",
"1.0.0+dfsg1-3~bpo13+1",
"1.0.0+dfsg1-4",
"1.0.0+dfsg1-5",
"1.1.0+dfsg-1~exp1",
"1.1.2+dfsg-1",
"1.1.2+dfsg-1~exp1",
"1.1.2+dfsg-2",
"1.1.2+really1.1.0+dfsg-1",
"1.1.2-1+really1.1.0+dfsg-1",
"1.1.2-1+really1.1.0+dfsg-2",
"1.1.3+dfsg-1",
"1.1.3+dfsg-2",
"1.1.3+dfsg-3",
"1.1.3+dfsg-4"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23879.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "py7zr",
"purl": "pkg:deb/debian/py7zr?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"0.22.0+dfsg-1",
"1.0.0+dfsg1-1",
"1.0.0+dfsg1-2",
"1.0.0+dfsg1-3",
"1.0.0+dfsg1-3~bpo13+1",
"1.0.0+dfsg1-4",
"1.0.0+dfsg1-5",
"1.1.0+dfsg-1~exp1",
"1.1.2+dfsg-1",
"1.1.2+dfsg-1~exp1",
"1.1.2+dfsg-2",
"1.1.2+really1.1.0+dfsg-1",
"1.1.2-1+really1.1.0+dfsg-1",
"1.1.2-1+really1.1.0+dfsg-2",
"1.1.3+dfsg-1",
"1.1.3+dfsg-2",
"1.1.3+dfsg-3",
"1.1.3+dfsg-4"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23879.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1.1.2+dfsg-1"
}
]
}
],
"package": {
"name": "py7zr",
"purl": "pkg:deb/debian/py7zr?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"0.22.0+dfsg-1",
"1.0.0+dfsg1-1",
"1.0.0+dfsg1-2",
"1.0.0+dfsg1-3",
"1.0.0+dfsg1-3~bpo13+1",
"1.0.0+dfsg1-4",
"1.0.0+dfsg1-5",
"1.1.0+dfsg-1~exp1",
"1.1.2+dfsg-1~exp1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23879.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #56228 · Revision 1
- Added to Heist Feed
- Publisher date