#VU24176 Cryptographic issues in Nimbus JOSE+JWT - CVE-2017-12973

Vulnerability identifier: #VU24176

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-12973

CWE-ID: CWE-310

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Nimbus JOSE+JWT
Universal components / Libraries / Libraries used by multiple products

Vendor: Connect2id Ltd.

Description

The vulnerability allows a remote attacker to conduct a padding oracle attack.

the vulnerability exists due to improper validation of HMAC in authenticated AES-CBC decryption in Nimbus JOSE+JWT. A remote attacker can conduct a padding oracle attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Nimbus JOSE+JWT: 4.0 - 4.39

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External links
http://bitbucket.org/connect2id/nimbus-jose-jwt/commits/6a29f10f723f406eb25555f55842c59a43a38912
http://bitbucket.org/connect2id/nimbus-jose-jwt/issues/223/aescbc-return-immediately-on-invalid-hmac
http://bitbucket.org/connect2id/nimbus-jose-jwt/src/master/CHANGELOG.txt

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.