Overview
- 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.
- Source
- security@duo.com
- NVD status
- Analyzed
Risk scores
CVSS 3.0
- Type
- Primary
- Base score
- 7.5
- Impact score
- 3.6
- Exploitability score
- 3.9
- Vector string
- CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Severity
- HIGH
CVSS 2.0
- Type
- Primary
- Base score
- 5
- Impact score
- 2.9
- Exploitability score
- 10
- Vector string
- AV:N/AC:L/Au:N/C:N/I:P/A:N
Weaknesses
- nvd@nist.gov
- NVD-CWE-noinfo
Social media
- Hype score
- Not currently trending
Configurations
[
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "2ED2491D-3EA6-4348-BABC-A1752F717260",
"versionEndIncluding": "1.5.0"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C11E6FB0-C8C0-4527-9AA0-CB9B316F8F43"
},
{
"criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252"
}
],
"operator": "OR"
}
]
}
]