CVE-2019-16782
Possible Information Leak / Session Hijack Vulnerability in Rack
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
- 5 years later
· 5 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.3 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N |
| NVDNVD · Modified | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 3.7% · top 10% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.3.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- RubyGemsrackGHSA-hrqr-hxpp-chr3 (opens in a new tab)
References (9)
- https://github.com/rack/rack/security/advisories/GHSA-hrqr-hxpp-chr3 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/rack/rack/commit/7fecaee81f59926b6e1913511c90650e76673b38 (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20191219 Re: [CVE-2019-16782] Possible Information Leak / Session Hijack Vulnerability in Rack (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20191218 [CVE-2019-16782] Possible Information Leak / Session Hijack Vulnerability in Rack (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20191218 Re: [CVE-2019-16782] Possible Information Leak / Session Hijack Vulnerability in Rack (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- FEDORA-2020-57fc0d0156 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- openSUSE-SU-2020:0214 (opens in a new tab)vendor-advisoryx_refsource_SUSEx_transferred
- [oss-security] 20200409 Re: [CVE-2019-16782] Possible Information Leak / Session Hijack Vulnerability in Rack (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20200408 Re: [CVE-2019-16782] Possible Information Leak / Session Hijack Vulnerability in Rack (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-hrqr-hxpp-chr3 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-16782)Record last updated .