Vulnerability in Google API C\+\+ Client
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.007 (49.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/google/google-api-cpp-client/pull/58 (Patch, Third Party Advisory, Issue Tracking)
- github.com/google/google-api-cpp-client/issues/57 (Exploit, Third Party Advisory, Issue Tracking)
Frequently asked questions
- What is CVE-2018-20840?
- CVE-2018-20840 is a high-severity vulnerability in Google API C\+\+ Client, classified under Improper Check for Unusual or Exceptional Conditions. CVSS score: 8.6/10. Published 2019-05-30.
- How severe is CVE-2018-20840?
- High severity. CVSS v3 base score is 8.6 out of 10.