Vulnerability identifier: #VU24176

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

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

---

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

---

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.