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.
CVE-2024-3094
“—” beside the score: it is equal to NVD's CVSS score.
Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2024-03-29. NVD baseline CVSS 10.0; sources differ by 0.0.
Also known asEUVD-2024-31700 (ENISA EUVD) · GHSA-rxwq-x6h5-x525 (GitHub Security Advisories)Source: ENISA EUVD
- High exploitation likelihood — EPSS 91%
- Public exploit or proof-of-concept code is available
A fix is available — apply it.
- CVSS v3
- 10.0
- EG Score
- 10.0CRITICALmedium confidence
- EG Risk
- 96EG Risk 96/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity100% × 45%Impact severity (EG Severity): CVSS 10.0 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation91% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability100% × 15%CISA's SSVC Automatable value: yes (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- 91%
- EPSS %ILE
- 99th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (10.0): severity, escalated by confirmed exploitation. This CVE's 10.0 is its impact severity (EG Severity), not escalated.
- EG Severity
- 10.0 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 91% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
March 29, 2024
Last Modified
August 4, 2026
Advisory Details (10)
Auto-updated Oct 27, 2026Urgent security alert for Fedora 40 and Fedora Rawhide users
https://www.redhat.com/en/blog/urgent-security-alert-fedora-41-and-rawhide-usersoss-security - backdoor in upstream xz/liblzma leading to ssh server compromise
https://www.openwall.com/lists/oss-security/2024/03/29/42272210 – (CVE-2024-3094) CVE-2024-3094 xz: malicious code in distributed source
https://bugzilla.redhat.com/show_bug.cgi?id=2272210CVE-2024-3094 - Red Hat Customer Portal
Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a
https://access.redhat.com/security/cve/CVE-2024-3094oss-security - Re: backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/30/12oss-security - Re: backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/29/8oss-security - Re: backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/29/5oss-security - backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/29/4oss-security - Re: backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/29/12oss-security - Re: backdoor in upstream xz/liblzma leading to ssh server compromise
http://www.openwall.com/lists/oss-security/2024/03/29/10Vendor Advisories for CVE-2024-3094(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(11 across 11 ecosystems)
Alpine:v3.15(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| lighttpd | — |
| — |
Alpine:v3.16(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| lighttpd | — |
| — |
Alpine:v3.17(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| lighttpd | — |
| — |
Alpine:v3.18(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| lighttpd | — |
| — |
Alpine:v3.20(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz | — |
| — |
Alpine:v3.21(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz | — |
| — |
Alpine:v3.22(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz | — |
| — |
Alpine:v3.23(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz | — |
| — |
Alpine:v3.24(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz | — |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz-utils | — |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| xz-utils | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 18× in last 7d / 57× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
Showing the most recent 96 of 127 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 4 repeat rows among the latest 100 are merged into the row they repeat. The 31 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-11-02 12:36 UTCEG score recompute
- 2026-11-02 12:35 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-11-01 12:58 UTCEG score recompute
- 2026-11-01 12:58 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-31 13:21 UTCEG score recompute
- 2026-10-31 13:21 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-30 13:44 UTCEG score recompute
- 2026-10-30 13:44 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-29 16:30 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-29 13:52 UTCEG score recompute
- 2026-10-29 13:52 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-28 14:15 UTCEG score recompute
- 2026-10-28 14:14 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-27 16:29 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-27 14:18 UTCEG score recompute
- 2026-10-27 14:18 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-26 14:19 UTCEG score recompute
- 2026-10-26 14:19 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-25 16:30 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-25 14:11 UTCEG score recompute
- 2026-10-25 14:11 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-24 14:34 UTCEG score recompute
- 2026-10-24 14:34 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-23 14:57 UTCEG score recompute
- 2026-10-23 14:57 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
Show 71 moreShow fewer
- 2026-10-22 16:31 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-22 15:19 UTCEG score recompute
- 2026-10-22 15:18 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-21 15:38 UTCEG score recompute
- 2026-10-21 15:38 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-20 16:30 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-20 16:01 UTCEG score recompute
- 2026-10-20 16:01 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-19 16:23 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-18 16:43 UTCEG score recompute
- 2026-10-18 16:43 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-18 07:18 UTCEG score recompute
- 2026-10-17 23:40 UTCEG score recompute
- 2026-10-17 23:40 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-17 00:03 UTCEG score recompute
- 2026-10-17 00:03 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-16 16:36 UTCEPSS rescoreEPSS 91% · 99th percentile
- 2026-10-15 20:57 UTCEG score recompute
- 2026-10-15 20:56 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-14 16:30 UTCEPSS rescoreEPSS 90% · 99th percentile
- 2026-10-14 15:04 UTCEG score recompute
- 2026-10-14 15:03 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-13 16:30 UTCEPSS rescoreEPSS 90% · 99th percentile
- 2026-10-13 14:25 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-12 17:56 UTCEG score recompute
- 2026-10-12 14:27 UTCEG score recompute
- 2026-10-12 14:27 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-10-11 21:20 UTCEG score recompute
- 2026-10-11 16:14 UTCEG score recompute
- 2026-10-10 19:58 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-10-07 23:46 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-10-03 14:24 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-30 19:42 UTCEG score recompute
- 2026-09-26 15:57 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-26 00:23 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-25 08:06 UTCOSV refresh
- 2026-09-24 14:01 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-22 14:46 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-21 20:32 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-18 19:26 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-16 14:06 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-07 15:59 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-06 13:46 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-05 23:51 UTCOSV refresh
- 2026-09-05 15:26 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-09-04 05:05 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-30 19:15 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-28 21:39 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-26 14:44 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-24 14:15 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-20 22:53 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-19 10:59 UTCOSV refresh
- 2026-08-18 13:46 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-13 21:59 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-11 13:40 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-04 15:08 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-08-04 06:38 UTCEG score recompute
- 2026-08-04 06:37 UTCGHSA enrichmentGHSA-rxwq-x6h5-x525 · GitHub severity CRITICAL · GitHub CVSS 10.0
- 2026-07-30 12:14 UTCOSV refresh
- 2026-07-24 14:16 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-23 02:36 UTCEG score recompute
- 2026-07-22 14:07 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-20 17:06 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-15 16:56 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-13 22:29 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-12 21:37 UTCOSV refresh
- 2026-07-12 05:45 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-06 02:22 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-07-01 15:05 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-06-25 13:49 UTCEPSS rescoreEPSS 86% · 99th percentile
- 2026-06-24 07:20 UTCOSV refresh
Publicly available exploits
(13 references, 10 shown)Public exploit code is referenced for this CVE (10 GitHub PoCs), as are 3 GitHub checker repositories. A GitHub repository named or described as a checker or scanner checks whether a system is affected; it is not necessarily exploit code. Defenders should treat patch urgency accordingly.
- GitHub PoCamlweems/xzbot✓ verifiedPublished Apr 2, 2024
Reverse-engineered honeypot + reproduction harness for the xz-utils backdoor.
Open source ↗ - GitHub PoCrobertdfrench/ifuncd-upPublished Jul 5, 2024
GNU IFUNC is the real culprit behind CVE-2024-3094
Open source ↗ - GitHub PoCr0binak/xzk8sPublished Apr 2, 2024
Dockerfile and Kubernetes manifests for reproduce CVE-2024-3094
Open source ↗ - GitHub PoC0xlane/xz-cve-2024-3094Published Apr 1, 2024
XZ Backdoor Extract(Test on Ubuntu 23.10)
Open source ↗ - Open source ↗GitHub PoCjfrog/cve-2024-3094-toolsPublished Mar 31, 2024
- GitHub checkerteyhouse/CVE-2024-3094Published Mar 30, 2024
K8S and Docker Vulnerability Check for CVE-2024-3094
Open source ↗ - Open source ↗GitHub checkerwgetnz/CVE-2024-3094-checkPublished Mar 30, 2024
- GitHub PoCemirkmo/xz-backdoor-githubPublished Mar 30, 2024
History of commits related to the xz backdoor Discovered On March 29, 2024: CVE-2024-3094.
Open source ↗ - GitHub PoCgensecaihq/CVE-2024-3094-Vulnerability-Checker-FixerPublished Mar 30, 2024
Shell scripts to identify and fix installations of xz-utils affected by the CVE-2024-3094 vulnerability. Versions 5.6.0 and 5.6.1 of xz-utils are known to be vulnerable, and this script aids in detecting them and optionally downgrading to a stable, un-compromised version (5.4.6) or upgrading to latest version. Added Ansible Playbook
Open source ↗ - GitHub PoClockness-Ko/xz-vulnerable-honeypotPublished Mar 30, 2024
An ssh honeypot with the XZ backdoor. CVE-2024-3094
Open source ↗
Past incidents using this CVE
(1)This CVE was central to one or more publicly-documented breaches. Each card links to authoritative reporting at the time of the incident.
- xz-utils backdoorMar 2024
Multi-year social-engineering attack inserted a backdoor into xz-utils, used by sshd via systemd. Caught accidentally by a Microsoft engineer before reaching stable Debian/Ubuntu. Closest call in OSS supply-chain history.
Source: Ars Technica
Related CVEs(same product + same CWE)
Same product
7 shownAlpine:v3.20:xz · Alpine:v3.18:lighttpd · Alpine:v3.15:lighttpd
Same CWE
10 shownCWE-506
- CVE-2024-4978NVD 8.4EG 9.0 KEVEPSS p98CRITICAL
- CVE-2023-2003EG 9.1CRITICAL
- CVE-2025-30066NVD 8.6EG 9.0 KEVEPSS p99CRITICAL
- CVE-2025-30154NVD 8.6EG 9.0 KEVCRITICAL
- CVE-2025-32965EG 9.3CRITICAL
- CVE-2025-54313NVD 7.5EG 9.0 KEVEPSS p92CRITICAL
- CVE-2025-8217EG 4.0MEDIUM
- CVE-2025-59037EG 8.6HIGH
- CVE-2025-59038EG 8.6HIGH
- CVE-2025-59039EG 9.3CRITICAL
Frequently asked(5)
What is CVE-2024-3094?
When was CVE-2024-3094 made public?
Is CVE-2024-3094 actively exploited?
What is the CVSS score of CVE-2024-3094?
How do I remediate CVE-2024-3094?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2024-3094
Is Your Infrastructure Affected by CVE-2024-3094?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.