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Public proof of conceptFix available

CVE-2026-102270

A public proof of concept exists; no exploitation attested.

  • Published2026-09-28
  • Fixed in2.14.0
  • WeaknessCWE-1333

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT is_pem_format is affected because lazy PEM regular expression backtracks extensively. This occurs when a certificate-like input contains repeated BEGIN markers without a matching END marker. As a result, is_pem_format performs unbounded backtracking while searching for a PEM end marker. Consequently, an attacker can cause intensive CPU consumption. This issue is fixed in version 2.14.0.

Timeline

dates in UTC
  1. 2026-09-2821:17CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-102270?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-102270?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV
Pyjwt project pyjwt
BranchAffectedFixed in
2.14< 2.14.02.14.0

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • CVE-2026-102270 Red Hat Product Security8 products fixed · 202 known affected

    pyjwt: pyjwt: Denial of Service via regular expression backtracking in is_pem_format

    ansible-automation-platform/automation-orchestrator-backend-rhel9 as a component of Ansible Automation Orchestrator 2026 · openshift-sandboxed-containers/osc-podvm-builder-rhel9 as a component of Confidential Compute Attestation · workload-availability/fence-agents-remediation-rhel9-operator as a component of Fence Agents Remediation Operator · +199 more

  • RHSA-2026:82415 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat AI Inference 3.5.2 (cpu)

  • RHSA-2026:82371 Red Hat Product Security3 products fixed

    Red Hat Security Advisory: Red Hat AI Inference 3.5.2 (spyre)

  • RHSA-2026:82368 Red Hat Product Security2 products fixed

    Red Hat Security Advisory: Red Hat AI Inference 3.5.2 (cuda)

  • RHSA-2026:82061 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat AI Inference Tech Preview 3.5.2 (Gaudi)

  • RHSA-2026:82059 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat AI Inference 3.5.2 (ROCm)

Full record on NVD

Fix

  1. Update Pyjwt project pyjwt to 2.14.0
  2. Vendor fix Red Hat Product Security RHSA-2026:82415 · 1 productFor more information visit https://access.redhat.com/errata/RHSA-2026:82415
  3. Vendor fix Red Hat Product Security RHSA-2026:82371 · 3 productsFor more information visit https://access.redhat.com/errata/RHSA-2026:82371
  4. Vendor fix Red Hat Product Security RHSA-2026:82368 · 2 productsFor more information visit https://access.redhat.com/errata/RHSA-2026:82368
  5. Vendor fix Red Hat Product Security RHSA-2026:82061 · 1 productFor more information visit https://access.redhat.com/errata/RHSA-2026:82061
  6. Vendor fix Red Hat Product Security RHSA-2026:82059 · 1 productFor more information visit https://access.redhat.com/errata/RHSA-2026:82059
  7. Workaround from the vendor Red Hat Product Security RHSA-2026:82415 · 1 productMitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CISA-ADPSSVC decisionpoc2026-09-29
  • OpenCVESSVC decisionpoc—
  • CNACVSS 3.14.4read 2026-10-23
  • NVDCVSS 3.14.9read 2026-10-23
  • CNAweakness (CWE)CWE-1333read 2026-10-23
  • FIRST EPSSEPSS score0.2 %2026-10-22
  • OSVaffected packages—

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Published
2026-09-28
Last Modified
2026-10-06
NVD status
Analyzed

Frequently asked questions

What is CVE-2026-102270?

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT is_pem_format is affected because lazy PEM regular expression backtracks extensively. This occurs when a certificate-like input contains repeated BEGIN markers without a matching END marker. As a result, is_pem_format performs unbounded backtracking while searching for a PEM end marker. Consequently, an attacker can cause intensive CPU consumption. This issue is fixed in version 2.14.0.

Is CVE-2026-102270 actively exploited?

A proof-of-concept exploit exists for CVE-2026-102270, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2026-102270?

CVE-2026-102270 has a CVSS v3 base score of 4.9 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H.

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