Description
Malicious code was discovered in the upstream tarballs of xz, starting with version 5.6.0. Through a series of complex obfuscations, the liblzma build process extracts a prebuilt object file from a disguised test file existing in the source code, which is then used to modify specific functions in the liblzma code. This results in a modified liblzma library that can be used by any software linked against this library, intercepting and modifying the data interaction with this library.
Affected products
tukaani: xz
References10
- access.redhat.com/security/cve/CVE-2024-3094 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2272210 Issue TrackingVendor Advisory
- www.redhat.com/en/blog/urgent-security-alert-fedora-41-and-rawh… Vendor Advisory
- access.redhat.com/security/cve/CVE-2024-3094 Vendor Advisory
- bugs.debian.org/cgi-bin/bugreport.cgi?bug=1068024 Mailing ListVendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2272210 Issue TrackingVendor Advisory
- tukaani.org/xz-backdoor/ Issue TrackingVendor Advisory
- www.redhat.com/en/blog/urgent-security-alert-fedora-41-and-rawh… Vendor Advisory
- www.openwall.com/lists/oss-security/2024/03/29/4 Mailing List
- www.openwall.com/lists/oss-security/2024/03/29/10
Metrics
- CVSS 3.1
-
10.0
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 91% percentile: 100 · as of 5 November 2026
- CWE
- CWE-506
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