CVE-2020-28042: Vulnerability Analysis & Exploit Details

CVE-2020-28042 Vulnerability Summary

ServiceStack before 5.9.2 mishandles JWT signature verification unless an application has a custom ValidateToken function that establishes a valid minimum length for a signature.

CVE-2020-28042: Detailed Information and External References

EPSS

0.00262

EPSS %

0.65534

References

0.00262

• https://forums.servicestack.net/t/servicestack-v5-9-2-released/8850
• https://github.com/ServiceStack/ServiceStack/commit/540d4060e877a03ae95343c1a8560a26768585ee
• https://www.shielder.it/advisories/servicestack-jwt-signature-verification-bypass/
• https://www.shielder.it/blog/2020/11/re-discovering-a-jwt-authentication-bypass-in-servicestack/

CWE

CWE-347

CAPEC

0.00262

• Padding Oracle Crypto Attack: An adversary is able to efficiently decrypt data without knowing the decryption key if a target system leaks data on whether or not a padding error happened while decrypting the ciphertext. A target system that leaks this type of information becomes the padding oracle and an adversary is able to make use of that oracle to efficiently decrypt data without knowing the decryption key by issuing on average 128*b calls to the padding oracle (where b is the number of bytes in the ciphertext block). In addition to performing decryption, an adversary is also able to produce valid ciphertexts (i.e., perform encryption) by using the padding oracle, all without knowing the encryption key.
• Signature Spoofing by Improper Validation: An adversary exploits a cryptographic weakness in the signature verification algorithm implementation to generate a valid signature without knowing the key.

Vulnerable Configurations

• cpe:2.3:a:servicestack:servicestack:4.0.10:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.10:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.17:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.17:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.18:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.18:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.19:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.19:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.20:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.20:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.21:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.21:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.22:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.22:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.23:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.23:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.24:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.24:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.30:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.30:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.31:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.31:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.32:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.32:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.33:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.33:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.34:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.34:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.35:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.35:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.36:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.36:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.38:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.38:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.42:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.42:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.44:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.44:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.46:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.46:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.48:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.48:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.50:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.50:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.52:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.52:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.54:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.54:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.56:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.56:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.58:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.58:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.60:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.60:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.0.62:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.0.62:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.0:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.0:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.2:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.2:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.4:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.4:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.6:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.6:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.8:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.8:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.10:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.10:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.12:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.12:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:4.5.14:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:4.5.14:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5.0.2:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5.1.0:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5.2.0:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5.2.0:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5.4:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5.4:*:*:*:*:*:*:*
• cpe:2.3:a:servicestack:servicestack:5.5:*:*:*:*:*:*:*
  cpe:2.3:a:servicestack:servicestack:5.5:*:*:*:*:*:*:*

CVSS3 Source

nvd@nist.gov

CVSS3 Type

Primary

CVSS3 Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N