CVE-2017-11424
pyjwt - security update
7.5
HIGH
CVSS 3.1
EPSS 0.19%
Description
In PyJWT 1.5.0 and below the `invalid_strings` check in `HMACAlgorithm.prepare_key` does not account for all PEM encoded public keys. Specifically, the PKCS1 PEM encoded format would be allowed because it is prefaced with the string `-----BEGIN RSA PUBLIC KEY-----` which is not accounted for. This enables symmetric/asymmetric key confusion attacks against users using the PKCS1 PEM encoded public keys, which would allow an attacker to craft JWTs from scratch.
How to fix CVE-2017-11424
To remediate CVE-2017-11424, upgrade the affected package to a fixed version below.
- —upgrade to 1.4.2-1.1 or later
- —upgrade to 0.2.1-1+deb8u2 or later
- —upgrade to 1.5.1 or later
- —upgrade to 1.5.1 or later
Is CVE-2017-11424 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (4)
- from 0, < 1.4.2-1.1
- from 0, < 0.2.1-1+deb8u2
- from 0, < 1.5.1
- from 0, < 1.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |