CVE-2018-20840

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.

CVSS v3.0

8.6 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS v2.0

5.0 MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P

EPSS

0.65% chance of exploitation in the next 30 days, 49th percentile

Published

2019-05-30

Updated

2024-08-05

Proof-of-concept exploits (1)

• google/google-api-cpp-client/issues/57

References

• CVE Record
• NVD entry

Related

• CVE-2020-8887
• CVE-2020-8911
• CVE-2020-8912
• CVE-2021-22543
• CVE-2021-22555
• CVE-2021-39295