CVE-2018-20840

Public Exploit

Description

An unhandled exception vulnerability exists during Google Sign-In with Google API C++ Client before 2019-04-10. It potentially causes an outage of third-party services that were not designed to recover from exceptions. On the client, ID token handling can cause an unhandled exception because of misinterpretation of an integer as a string, resulting in denial-of-service and then other users can no longer login/sign-in to the affected third-party service. Once this third-party service uses Google Sign-In with google-api-cpp-client, a malicious user can trigger this client/auth/oauth2_authorization.cc vulnerability by requesting the client to receive the ID token from a Google authentication server.

Category

8.6
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.18%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/google/google-api-cpp-client/pull/58 patch third party advisory issue tracking
https://github.com/google/google-api-cpp-client/issues/57 third party advisory issue tracking exploit

Frequently Asked Questions

What is the severity of CVE-2018-20840?
CVE-2018-20840 has been scored as a high severity vulnerability.
How to fix CVE-2018-20840?
To fix CVE-2018-20840, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-20840 being actively exploited in the wild?
It is possible that CVE-2018-20840 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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