CVE-2019-16782 — There's a possible information leak / session hijack vulnerability in Rack (Ruby

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

01What is this vulnerability?

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…

02Affected products

Vendor	Product	Versions
rack	rack	before 1.6.12 or 2.0.8

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-12-18T19:05:14.000Z
• Last modified: 2024-08-05T01:24:48.031Z

09References

• github.com — https://github.com/rack/rack/security/advisories/GHSA-hrqr-hxpp-chr3
• github.com — https://github.com/rack/rack/commit/7fecaee81f59926b6e1913511c90650e76673b38
• www.openwall.com — http://www.openwall.com/lists/oss-security/2019/12/18/3
• www.openwall.com — http://www.openwall.com/lists/oss-security/2019/12/18/2
• www.openwall.com — http://www.openwall.com/lists/oss-security/2019/12/19/3
• lists.fedoraproject.org — https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedorapro…
• lists.opensuse.org — http://lists.opensuse.org/opensuse-security-announce/2020-02/msg00016.html
• www.openwall.com — http://www.openwall.com/lists/oss-security/2020/04/08/1
• www.openwall.com — http://www.openwall.com/lists/oss-security/2020/04/09/2