CyberSecBulletin
CVE-2026-4926NVD status: Modified

path-to-regexp: Uncontrolled Resource Consumption

Published Updated By the CyberSecBulletin desk

CVE-2026-4926 is a high-severity uncontrolled resource consumption vulnerability in path-to-regexp, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 8.4.0 as the first without the flaw, so updating path-to-regexp to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.82% chance of exploitation within 30 days, higher than 58% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update path-to-regexp to 8.4.0 or a later version.
  2. Read the advisory on cna.openjsf.org for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Path-to-regexppath-to-regexp8.0.0 up to, but not including, 8.4.08.4.0
Red HatCryostat 4 on RHEL 9Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.5 for RHEL 8Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.5 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.6 for RHEL 9Not specified in the recordNot stated
Red HatMigration Toolkit for Virtualization 2.1Not specified in the recordNot stated
Red HatMigration Toolkit for Virtualization 2.9Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.6Not specified in the recordNot stated
Red HatRed Hat Developer Hub 1.8Not specified in the recordNot stated
Red HatRed Hat Developer Hub 1.9Not specified in the recordNot stated
Red HatRed Hat Edge Manager 1.0Not specified in the recordNot stated
Red HatRed Hat Edge Manager 1.1Not specified in the recordNot stated
Red HatRed Hat Migration Toolkit for Applications 8.1Not specified in the recordNot stated
Red HatRed Hat OpenShift AI 2.25Not specified in the recordNot stated
Red HatRed Hat OpenShift Dev Spaces 3.27Not specified in the recordNot stated
Red HatRed Hat OpenShift distributed tracing 3.9.3Not specified in the recordNot stated
Red HatRed Hat Trusted Artifact Signer 1.3Not specified in the recordNot stated
Red HatCryostat 4Not specified in the recordNot stated
Red HatLogging Subsystem for Red Hat OpenShiftNot specified in the recordNot stated
Red HatMulticluster Engine for KubernetesNot specified in the recordNot stated
Red HatNetwork Observability OperatorNot specified in the recordNot stated
Red HatOpenShift LightspeedNot specified in the recordNot stated
Red HatOpenShift PipelinesNot specified in the recordNot stated
Red HatOpenShift Service Mesh 2Not specified in the recordNot stated
Red HatOpenShift Service Mesh 3Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 27 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA
CVSS 3.17.5HighCNA

Official description

Impact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Uncontrolled Resource Consumption

The product does not properly control the allocation and maintenance of a limited resource.

How developers prevent this class of flaw

  • Ensure that protocols have specific limits of scale placed on them.
  • Ensure that all failures in resource allocation place the system into a safe posture.

More Uncontrolled Resource Consumption vulnerabilities (CWE-400)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Advisories

Other vulnerabilities in path-to-regexp

All path-to-regexp vulnerabilities

Recent Uncontrolled Resource Consumption vulnerabilities

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