---
id: CVE-2026-101917
title: PyJWT is a Python implementation of JSON Web Token standards
summary: >-
  PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0,
  PyJWT get_signing_key_from_jwt is affected because unknown kid misses force
  refreshes without a negative cache or minimum refresh interval. This occurs
  when u…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-770
  - CWE-408
vendor: pyjwt_project
product: pyjwt
affected:
  - pyjwt < 2.14.0
patched:
  - pyjwt 2.14.0
published: '2026-09-28'
updated: '2026-10-07'
sourceUpdated: '2026-10-07T21:01:01.010'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-101917'
references:
  - url: >-
      https://github.com/jpadilla/pyjwt/commit/ba4853a75fb9676362da17f67d0f64bd18afd4e1
    label: security-advisories@github.com
  - url: 'https://github.com/jpadilla/pyjwt/releases/tag/2.14.0'
    label: security-advisories@github.com
  - url: 'https://github.com/jpadilla/pyjwt/security/advisories/GHSA-2gx3-rcp4-g85q'
    label: security-advisories@github.com
  - url: 'https://github.com/jpadilla/pyjwt/security/advisories/GHSA-2gx3-rcp4-g85q'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-101917.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-101917'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2542677'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-101917'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-101917'
  - url: 'https://github.com/advisories/GHSA-2gx3-rcp4-g85q'
  - url: 'https://github.com/jpadilla/pyjwt'
  - url: 'https://pypi.org/project/pyjwt'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82415'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82368'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82061'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82059'
  - url: 'https://access.redhat.com/errata/RHSA-2026:82371'
tags:
  - nvd
  - cve.org
  - exploit-available
  - csaf
  - vex
  - red-hat
  - ghsa
  - pip
  - osv
epss: 0.00428
epssPercentile: 0.3683
aliases:
  - GHSA-2gx3-rcp4-g85q
  - PYSEC-2026-4140
ecosystem: pip
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-28T20:35:19.525335Z'
ingestedAt: '2026-09-28T21:20:54.777Z'
---

## Overview

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT get_signing_key_from_jwt is affected because unknown kid misses force refreshes without a negative cache or minimum refresh interval. This occurs when unauthenticated tokens repeatedly use the same unknown kid or varying kid values absent from the cached JWKS. As a result, each cache miss causes PyJWKClient to refresh the JWKS. Consequently, attacker traffic can amplify outbound requests to the configured JWKS endpoint. This issue is fixed in version 2.14.0.

## Affected

- `pyjwt < 2.14.0`

## Remediation

Upgrade past the affected range:

- `pyjwt 2.14.0`

## Package advisory (CVE-2026-101917)

Affected packages:

- `pyjwt <= 2.13.0`

Patched in:

- `pyjwt 2.14.0`

Source: https://github.com/advisories/GHSA-2gx3-rcp4-g85q

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Ansible Automation Orchestrator 2026, Confidential Compute Attestation, Fence Agents Remediation Operator, Lightspeed Core, Migration Toolkit for Applications 8, OpenShift Lightspeed, … · no fix planned: Ansible Automation Orchestrator 2026, Confidential Compute Attestation, Fence Agents Remediation Operator, Lightspeed Core, … · updated 2026-10-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-101917.json)
- **RHSA-2026:82415** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82415)
- **RHSA-2026:82368** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82368)
- **RHSA-2026:82061** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82061)
- **RHSA-2026:82059** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82059)
- **RHSA-2026:82371** · Red Hat · fixed in: Red Hat AI Inference Server 3.5 · released 2026-10-13 · [advisory](https://access.redhat.com/errata/RHSA-2026:82371)