Vulnerability in Rack

CVE-2019-16782

There's a possible information leak / session hijack vulnerability in Rack (RubyGem rack). This vulnerability is patched in versions 1.6.12 and 2.0.8. Attackers may be able to find and hijack sessions by using timing attacks targeting the session id. Session ids are usually stored and indexed in a database that uses some kind of scheme for speeding up lookups of that session id. By carefully measuring the amount of time it takes to look up a session, an attacker may be able to find a valid session id and hijack the session. The session id itself may be generated randomly, but the way the session is indexed by the backing store does not use a secure comparison.

EPSS: 0.037 (88.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-16782?
CVE-2019-16782 is a medium-severity vulnerability in Rack, classified under CWE-208. CVSS score: 6.3/10. Published 2019-12-18.
How severe is CVE-2019-16782?
Medium severity. CVSS v3 base score is 6.3 out of 10.