#VU72076 Incorrect authorization in Google API Client Library for Java - CVE-2020-7692

Vulnerability identifier: #VU72076

Vulnerability risk: High

CVSSv4.0: 8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2020-7692

CWE-ID: CWE-863

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Google API Client Library for Java
Universal components / Libraries / Libraries used by multiple products

Vendor: Google

Description

The vulnerability allows a remote attacker to bypass authorization process.

The vulnerability exists due to missing support for PKCE. Without the use of PKCE, the authorization code returned by an authorization server is not enough to guarantee that the client that issued the initial authorization request is the one that will be authorized. An attacker is able to obtain the authorization code using a malicious app on the client-side and use it to gain authorization to the protected resource.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Google API Client Library for Java: before 1.31.0

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External links
https://github.com/googleapis/google-oauth-java-client/commit/13433cd7dd06267fc261f0b1d4764f8e3432c824
https://github.com/googleapis/google-oauth-java-client/issues/469
https://tools.ietf.org/html/rfc8252%23section-8.1
https://tools.ietf.org/html/rfc7636%23section-1
https://snyk.io/vuln/SNYK-JAVA-COMGOOGLEOAUTHCLIENT-575276
https://lists.apache.org/thread.html/r3db6ac73e0558d64f0b664f2fa4ef0a865e57c5de20f8321d3b48678@%3Ccommits.druid.apache.org%3E
https://lists.apache.org/thread.html/reae8909b264d1103f321b9ce1623c10c1ddc77dba9790247f2c0c90f@%3Ccommits.druid.apache.org%3E

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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.