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Fencer Vulns
high 7.5

CVE-2026-32829 json

lz4_flex: Decompression can leak information from uninitialized memory or reused output buffer

published 2026-03-16 7 mo ago modified 2026-09-17 53 d ago also GHSA-vvp9-7p8x-rfvv , RUSTSEC-2026-0041 , EUVD-2026-13426

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits
0
none known

Summary

lz4_flex is a pure Rust implementation of LZ4 compression/decompression. In versions 0.11.5 and below, and 0.12.0, decompressing invalid LZ4 data can leak sensitive information from uninitialized memory or from previous decompression operations. The library fails to properly validate offset values during LZ4 "match copy operations," allowing out-of-bounds reads from the output buffer. The block-based API functions (`decompress_into`, `decompress_into_with_dict`, and others when `safe-decode` is disabled) are affected, while all frame APIs are unaffected. The impact is potential exposure of sensitive data and secrets through crafted or malformed LZ4 input. This issue has been fixed in versions 0.11.6 and 0.12.1.

Patch / fix

  • crates.io lz4_flex 0.11.6, 0.12.1
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.2 1776894389
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.4 1780052069
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.5 1777574710
  • Red Hat Red Hat OpenShift AI 3.3 1778263962
  • rust-lz4-flex Debian 14 0.13.0-1

debian advisories DEBIAN-CVE-2026-32829

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
7 mo ago

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.2 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA 4.0 8.2 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
crates.io lz4_flex
<0.11.6
>=0.12.0, <0.12.1
>=0.0.0-0, <0.11.6
0.11.6
0.12.1

Affected products

  • PSeitz lz4_flex
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.2
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.4
  • Red Hat Logging Subsystem for Red Hat OpenShift 6.5
  • Red Hat Red Hat OpenShift AI 3.3
  • Red Hat OpenShift Lightspeed
  • Red Hat Red Hat Ansible Automation Platform 2
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat OpenShift AI (RHOAI)

Classification

Weakness
  • CWE-201 Insertion of Sensitive Information Into Sent Data
  • CWE-823 Use of Out-of-range Pointer Offset

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.