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Fencer Intel
medium 5.3

CVE-2025-68142 json

PyMdown Extensions has ReDOS bug in Figure Capture extension

published 10mo ago modified 4mo ago also EUVD-2025-203840 , GHSA-r6h4-mm7h-8pmq , PYSEC-2026-1825

cvss
5.3
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits
0
none known

Summary

PyMdown Extensions is a set of extensions for the `Python-Markdown` markdown project. Versions prior to 10.16.1 have a ReDOS bug found within the figure caption extension (`pymdownx.blocks.caption`). In systems that take unchecked user content, this could cause long hanges when processing the data if a malicious payload was crafted. This issue is patched in Release 10.16.1. As a workaround, those who process unknown user content without timeouts or other safeguards in place to prevent really large, malicious content being aimed at systems may avoid the use of `pymdownx.blocks.caption` until they're able to upgrade.

Patch / fix

  • pypi pymdown-extensions 10.16.1
  • facelessuser pymdown_extensions 10.16.1
  • pymdown_extensions_project pymdown_extensions 10.16.1
  • pymdown-extensions Debian 13 10.13-1+deb13u1
  • pymdown-extensions Debian 14 10.13-4

debian advisories DEBIAN-CVE-2025-68142

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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-2025-68142 updated cvss 5.3

PyMdown: pymdown-extensions: PyMdown Extensions: Regular Expression Denial of Service in figure caption extension

  • Red Hat Assisted Installer for Red Hat OpenShift Container Platform 2 rhai/assisted-installer-rhel9, rhai/assisted-installer-agent-rhel9, rhai/assisted-installer-controller-rhel9 Red Hat External Secrets Operator for Red Hat OpenShift external-secrets-operator/external-secrets-rhel9, external-secrets-operator/bitwarden-sdk-server-rhel9, external-secrets-operator/external-secrets-operator-rhel9, external-secrets-operator/external-secrets-operator-bundle Red Hat external secrets operator for Red Hat OpenShift - Tech Preview external-secrets-operator/external-secrets-rhel9, external-secrets-operator/bitwarden-sdk-server-rhel9, external-secrets-operator/external-secrets-operator-rhel9, external-secrets-operator/external-secrets-operator-bundle Red Hat Multicluster Engine for Kubernetes multicluster-engine/assisted-installer-rhel9, multicluster-engine/assisted-service-8-rhel8, multicluster-engine/assisted-service-9-rhel9, multicluster-engine/assisted-installer-agent-rhel9, multicluster-engine/assisted-installer-controller-rhel9 Red Hat OpenShift Service Mesh 2 openshift-service-mesh/pilot-rhel8, openshift-service-mesh/grafana-rhel8, openshift-service-mesh/proxyv2-rhel9, openshift-service-mesh/istio-cni-rhel8, openshift-service-mesh/ratelimit-rhel8, openshift-service-mesh/istio-rhel8-operator, +2 more Red Hat OpenShift Service Mesh 3 openshift-service-mesh/istio-cni-rhel9, openshift-service-mesh/istio-pilot-rhel9, openshift-service-mesh/istio-proxyv2-rhel9, openshift-service-mesh/istio-rhel9-operator, openshift-service-mesh/istio-must-gather-rhel9, openshift-service-mesh/istio-sail-operator-bundle, +1 more
    +1 more products
    Red Hat Advanced Cluster Security 4 advanced-cluster-security/rhacs-collector-rhel8
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Ceph Storage 6 pymdown Red Hat Ceph Storage 7 pymdown Red Hat Ceph Storage 8 rhceph/grafana-rhel9 Red Hat Ceph Storage 9 pymdown
    affected: workaround, no fix available
  • Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9 Red Hat OpenShift Container Platform 4 openshift4/ose-olm-catalogd-rhel8, openshift4/ose-olm-catalogd-rhel9, openshift4/ose-olm-operator-controller-rhel8, openshift4/ose-olm-operator-controller-rhel9, openshift4/ose-agent-installer-api-server-rhel9, openshift4/ose-agent-installer-node-agent-rhel9, +2 more Red Hat OpenShift Dev Spaces devspaces/traefik-rhel9 Red Hat OpenShift GitOps openshift-gitops-1/dex-rhel8, openshift-gitops-1/argocd-rhel8, openshift-gitops-1/argocd-rhel9, openshift-gitops-1/gitops-rhel8, openshift-gitops-1/must-gather-rhel8, openshift-gitops-1/argocd-agent-rhel8, +5 more
    affected: workaround, no fix available “Fix deferred”

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

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
10mo ago

Exploit prediction

0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/facelessuser/pymdown-extensions/security/advisories/GHSA-r6h4-mm7h-8pmq referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 2.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U
CNA 4.0 2.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/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 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem package affected fixed in
pypi pymdown-extensions
<10.16.1
10.16.1

Affected products

  • facelessuser pymdown-extensions

Classification

Weakness
  • CWE-1333 Inefficient Regular Expression Complexity

References

Sources

Fencer Intel 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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.