CVE-2026-39243: n/a
A vulnerability in decompress versions before 4.2.2 allows attackers to create arbitrary hardlinks during archive extraction. This occurs because the x.linkname field from hardlink entries is passed directly to fs.link() without validation. An attacker can craft an archive with a hardlink entry pointing to an absolute path on the same filesystem, resulting in a hardlink inside the extraction directory that shares the inode with the target file. This enables reading and overwriting the original file's content. Hardlinks cannot target directories and are limited to the same filesystem.
AI Analysis
Technical Summary
The decompress library versions prior to 4.2.2 contain a vulnerability where the handling of hardlink entries (type 'link') during archive extraction does not validate the x.linkname field before passing it to fs.link(). This allows an attacker to create a hardlink inside the extraction directory that points to any file on the same filesystem by specifying an absolute path. Consequently, this can lead to unauthorized file read disclosure and file corruption by overwriting the original file's content. The vulnerability is limited to files on the same filesystem and does not affect directories.
Potential Impact
Exploitation of this vulnerability can lead to unauthorized disclosure of file contents and corruption of files on the affected system by creating hardlinks that share inodes with target files. This can compromise data integrity and confidentiality within the filesystem where the archive is extracted.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should avoid extracting archives from untrusted sources with decompress versions before 4.2.2 until an official fix or mitigation is available.
CVE-2026-39243: n/a
Description
A vulnerability in decompress versions before 4.2.2 allows attackers to create arbitrary hardlinks during archive extraction. This occurs because the x.linkname field from hardlink entries is passed directly to fs.link() without validation. An attacker can craft an archive with a hardlink entry pointing to an absolute path on the same filesystem, resulting in a hardlink inside the extraction directory that shares the inode with the target file. This enables reading and overwriting the original file's content. Hardlinks cannot target directories and are limited to the same filesystem.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The decompress library versions prior to 4.2.2 contain a vulnerability where the handling of hardlink entries (type 'link') during archive extraction does not validate the x.linkname field before passing it to fs.link(). This allows an attacker to create a hardlink inside the extraction directory that points to any file on the same filesystem by specifying an absolute path. Consequently, this can lead to unauthorized file read disclosure and file corruption by overwriting the original file's content. The vulnerability is limited to files on the same filesystem and does not affect directories.
Potential Impact
Exploitation of this vulnerability can lead to unauthorized disclosure of file contents and corruption of files on the affected system by creating hardlinks that share inodes with target files. This can compromise data integrity and confidentiality within the filesystem where the archive is extracted.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should avoid extracting archives from untrusted sources with decompress versions before 4.2.2 until an official fix or mitigation is available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-04-06T00:00:00.000Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a50171468715ace431ea188
Added to database: 07/09/2026, 21:48:04 UTC
Last enriched: 07/09/2026, 22:05:21 UTC
Last updated: 07/09/2026, 23:59:13 UTC
Views: 4
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