Is CVE-2016-7036 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2016-7036 being exploited in the wild.

How severe is CVE-2016-7036?

Critical severity, with a CVSS score of 9.8, published 23 January 2017.

Which products and versions are affected?

python-jose (PyPI) ECOSYSTEM:introduced=0,fixed=1.3.2.

Is there a fix for CVE-2016-7036?

Yes. python-jose (PyPI): upgrade to 1.3.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2016-7036 attacked?

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

Am I affected by CVE-2016-7036?

Check whether you run python-jose (PyPI) or Python-Jose Project Python-Jose 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-2016-7036: python-jose timing attack in HMAC key comparison

CVE-2016-7036 · Severity: critical · CVSS 9.8 · Published 2017-01-23

The python-jose library, which is used to implement JSON Web Tokens (JWT) for secure data exchange and authentication, contains a vulnerability in how it verifies security keys. Because the library does not use a consistent amount of time to compare keys, an attacker could potentially guess valid security signatures by measuring response times. If successful, this could allow an attacker to bypass authentication, forge data, or gain unauthorized access to protected systems.

Technologies: python-jose (PyPI), Python-Jose Project Python-Jose. Vendors: PyPI, Python-Jose Project.

Quick answers

Is CVE-2016-7036 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2016-7036 being exploited in the wild.
How severe is CVE-2016-7036?: Critical severity, with a CVSS score of 9.8, published 23 January 2017.
Which products and versions are affected?: python-jose (PyPI) ECOSYSTEM:introduced=0,fixed=1.3.2.
Is there a fix for CVE-2016-7036?: Yes. python-jose (PyPI): upgrade to 1.3.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2016-7036 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2016-7036?: Check whether you run python-jose (PyPI) or Python-Jose Project Python-Jose 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

python-jose (PyPI): upgrade to 1.3.2 or later
```
pip install "python-jose>=1.3.2"
```

Technical details

The python-jose library prior to version 1.3.2 fails to use a constant-time string comparison algorithm when verifying HMAC signatures. This introduces a timing side-channel vulnerability (CWE-361) where the time taken to reject an invalid signature depends on how many initial bytes match the correct key. A remote, unauthenticated attacker can exploit this by measuring precise response times to iteratively guess the correct HMAC signature. Successful exploitation allows the attacker to forge valid JSON Web Tokens (JWTs), leading to complete authentication bypass and unauthorized data modification. The issue was resolved in version 1.3.2 by implementing constant-time comparison in the JWK component.

Affected products

mpdavis python-jose < 1.3.2

Identifiers

CVE-2016-7036
GHSA-w799-prg3-cx77
PYSEC-2017-28

Timeline

2016-09-05: patched: Fix merged into master and version 1.3.2 released.
2017-01-23: disclosed: NVD publication date.

References

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