Is CVE-2026-102268 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-102268 being exploited in the wild.

How severe is CVE-2026-102268?

Critical severity, with a CVSS score of 9.1, published 28 September 2026.

Which products and versions are affected?

PyJWT Project PyJWT prior to 2.14.0; pyjwt (PyPI) <= 2.13.0, ECOSYSTEM:introduced=0,fixed=2.14.0.

Is there a fix for CVE-2026-102268?

Yes. pyjwt (PyPI): upgrade to 2.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-102268 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-102268?

Check whether you run PyJWT Project PyJWT or pyjwt (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-102268: PyJWT HMAC signature forgery via PEM parsing bypass

Q: Is there a fix for CVE-2026-102268?

Yes. pyjwt (PyPI): upgrade to 2.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-102268 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-102268?

Check whether you run PyJWT Project PyJWT or pyjwt (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-102268 · Severity: critical · CVSS 9.1 · Published 2026-09-28

PyJWT is a Python library used to create and validate JSON Web Tokens (JWTs), a common method for securing API authentication and session management. An attacker who knows the public key can forge valid authentication tokens if the application mixes HMAC and asymmetric signing algorithms, allowing unauthorized access to protected resources or impersonation of legitimate users.

Technologies: pyjwt (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-102268 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-102268 being exploited in the wild.
How severe is CVE-2026-102268?: Critical severity, with a CVSS score of 9.1, published 28 September 2026.
Which products and versions are affected?: PyJWT Project PyJWT prior to 2.14.0; pyjwt (PyPI) <= 2.13.0, ECOSYSTEM:introduced=0,fixed=2.14.0.
Is there a fix for CVE-2026-102268?: Yes. pyjwt (PyPI): upgrade to 2.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-102268 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-102268?: Check whether you run PyJWT Project PyJWT or pyjwt (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

pyjwt (PyPI): upgrade to 2.14.0 or later
```
pip install "pyjwt>=2.14.0"
```

Technical details

The is_pem_format function in jwt/utils.py fails to recognize certain PEM representations that are accepted by the cryptography library's key loader. When an application supplies a mutated public-key PEM as raw bytes alongside HMAC algorithm support, the library incorrectly treats the asymmetric key as an HMAC secret. An attacker with knowledge of the public key can then forge valid HMAC-signed tokens. The vulnerability requires the application to mix HMAC and asymmetric algorithms and was patched in version 2.14.0.

Affected products

PyJWT Project PyJWT prior to 2.14.0

Identifiers

CVE-2026-102268
GHSA-ffc3-869f-jxw9
PYSEC-2026-4145

Timeline

2026-09-28: disclosed
2026-09: patched: Version 2.14.0 released

References

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