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Fencer Vulns
high 7.5

CVE-2021-29482 json

denial of service in github.com/ulikunitz/xz

published 2021-04-14 5 y ago modified 2026-07-08 4 mo ago also GHSA-25xm-hr59-7c27 , GO-2020-0016 , EUVD-2021-0896

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.4%
EPSS 1.4% chance of exploitation in 30 days, percentile 73%
public exploits
0
none known

Summary

xz is a compression and decompression library focusing on the xz format completely written in Go. The function readUvarint used to read the xz container format may not terminate a loop provide malicous input. The problem has been fixed in release v0.5.8. As a workaround users can limit the size of the compressed file input to a reasonable size for their use case. The standard library had recently the same issue and got the CVE-2020-16845 allocated.

Patch / fix

  • go github.com/ulikunitz/xz 0.5.8
  • xz_project xz 0.5.8
  • golang-github-ulikunitz-xz Debian 14, Debian 13, Debian 12 0.5.6-2

debian advisories DEBIAN-CVE-2021-29482

  • kiali service mesh 2.0 v1.24.7.redhat1-1.el8
  • servicemesh service mesh 2.0 2.0.9-3.el8
  • servicemesh-mixc service mesh 2.0 2.0.9-3.el8
  • servicemesh-mixs service mesh 2.0 2.0.9-3.el8
  • servicemesh-proxy service mesh 2.0 2.0.9-3.el8
  • servicemesh-istioctl service mesh 2.0 2.0.9-3.el8
  • servicemesh-prometheus service mesh 2.0 2.14.0-16.el8.1
  • servicemesh-pilot-agent service mesh 2.0 2.0.9-3.el8

red hat advisories RHSA-2022:1276

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-29482 updated cvss 7.5

ulikunitz/xz: Infinite loop in readUvarint allows for denial of service

  • Red Hat Migration Toolkit for Containers openshift-migration-plugin-container
    affected: no fix available
  • Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/openshift-hive-rhel8, rhacm2/search-collector-rhel8, rhacm2/search-collector-rhel9, rhacm2/multiclusterhub-rhel9-operator, multicloud-operators-channel-container, multicloud-operators-application-container, +1 more Red Hat OpenShift Container Platform 4 podman, skopeo, buildah, podman-tests, skopeo-tests, buildah-tests, +12 more
    affected: no fix available, no fix planned “Will not fix”
  • Red Hat OpenShift Virtualization 2 virt-cdi-importer-container, virt-cdi-uploadserver-container
    affected: no fix available
  • Red Hat OpenStack Platform 16.2 osp-director-provisioner-container, rhosp-rhel8-tech-preview/osp-director-downloader
    affected: no fix available, no fix planned “Will not fix”
  • Red Hat Quay 3 quay/clair-rhel8, quay/quay-builder-rhel8, quay/quay-operator-rhel8
    affected: no fix available
  • Red Hat CNV 4.8 for RHEL 8 container-native-virtualization/vm-import-operator-rhel8 v4.8.0-18
    fixed: vendor fix RHSA-2021:2920
  • Red Hat OpenShift API for Data Protection 1.0 oadp/oadp-velero-plugin-rhel8 1.0.1-5
    fixed: vendor fix RHSA-2022:0687
  • Red Hat OpenShift Service Mesh 2.0 servicemesh 2.0.9-3.el8, servicemesh-mixc 2.0.9-3.el8, servicemesh-mixs 2.0.9-3.el8, servicemesh-istioctl 2.0.9-3.el8, servicemesh-pilot-agent 2.0.9-3.el8, servicemesh-pilot-discovery 2.0.9-3.el8
    fixed: vendor fix RHSA-2022:1276
show 2 more
  • Red Hat OpenStack Platform 16.2 rhosp-rhel8-tech-preview/osp-director-operator 1.2.3-2
    fixed: vendor fix RHSA-2022:2183
  • Red Hat Migration Toolkit for Containers rhmtc/openshift-migration-controller-rhel8 Red Hat OpenShift API for Data Protection 1.0 oadp/oadp-velero-rhel8 1.0.1-5, oadp/oadp-registry-rhel8 1.0.1-3, oadp/oadp-rhel8-operator 1.0.1-6, oadp/oadp-mustgather-rhel8 1.0.1-7, oadp/oadp-operator-bundle 1.0.1-10, oadp/oadp-velero-plugin-for-aws-rhel8 1.0.1-4, +5 more Red Hat OpenShift Service Mesh 2.0 kiali v1.24.7.redhat1-1.el8, servicemesh-cni 2.0.9-3.el8, servicemesh-proxy 2.0.9-3.el8, servicemesh-operator 2.0.9-3.el8, servicemesh-prometheus 2.14.0-16.el8.1 Red Hat Advanced Cluster Management for Kubernetes 2 multicloud-operators-subscription, multicloud-operators-subscription-release, rhacm2/clusterlifecycle-state-metrics-rhel8 Red Hat OpenShift Container Platform 4 cri-o, openshift4/ose-docker-builder, openshift4/compliance-rhel8-operator, openshift4/ose-machine-config-operator, openshift4/file-integrity-rhel8-operator, openshift4/ose-cluster-node-tuning-rhel9-operator Red Hat OpenShift Container Platform Assisted Installer 1 rhai-tech-preview/assisted-installer-rhel8, rhai-tech-preview/assisted-installer-agent-rhel8, rhai-tech-preview/assisted-installer-reporter-rhel8
    +2 more products
    Red Hat OpenShift Virtualization 2 kubemacpool-container, virt-cdi-cloner-container, virt-cdi-operator-container, vm-import-virtv2v-container, virt-cdi-apiserver-container, vm-import-operator-container, +5 more Red Hat OpenStack Platform 16.2 rhosp-rhel8-tech-preview/osp-director-downloader 1.2.3-2, rhosp-rhel8-tech-preview/osp-director-operator-bundle 1.2.3-3
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.44% chance of exploitation in the next 30 days, higher than 73% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
go github.com/ulikunitz/xz
<0.5.8
0.5.8

Affected products

  • ulikunitz xz

Classification

Weakness
  • CWE-835 Loop with Unreachable Exit Condition

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.