CVE-2019-16782

MEDIUMNVD 6.36.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.3 under NVD CVSS v3. EPSS exploit probability: 0.9%, top 24% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
6.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 4%CVSS: 6.3Exploit: NoneExposed: 0

A fix is available — apply it.

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.

CVSS v3
6.3
EG Score
6.3(medium)
EPSS
88.4%
KEV
Not listed

Published

December 18, 2019

Last Modified

February 13, 2025

References (18)

Vendor Advisories for CVE-2019-16782(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubunturuby-rack (1.6.4-3ubuntu0.2+esm2) @ xenial2026-05-27ubuntu
redhattfm-rubygem-zeitwerk-0:2.2.2-1.el7sat2021-04-21redhat
redhatlibssh2-0:1.9.0-2.el8cf2020-06-10redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
RubyGems(1)
PackageVulnerable rangeFixed inDependents
rack2.0.1 ... 2.0.7 (7 versions)2.0.8—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(2)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 9× in last 7d / 40× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-11 08:24 UTCEPSS rescore
  2. 2026-07-11 08:24 UTCEPSS rescore
  3. 2026-07-09 19:06 UTCEPSS rescore
  4. 2026-07-08 15:11 UTCEPSS rescore
  5. 2026-07-07 13:43 UTCEPSS rescore
  6. 2026-07-06 16:25 UTCEPSS rescore
  7. 2026-07-06 16:25 UTCEPSS rescore
  8. 2026-07-06 02:20 UTCEPSS rescore
  9. 2026-07-05 02:27 UTCEPSS rescore
  10. 2026-07-04 06:28 UTCEPSS rescore
  11. 2026-07-02 14:01 UTCOSV refresh
  12. 2026-07-01 15:03 UTCEPSS rescore
  13. 2026-07-01 15:03 UTCEPSS rescore
  14. 2026-06-30 23:20 UTCEPSS rescore
  15. 2026-06-29 14:03 UTCEPSS rescore
  16. 2026-06-28 14:04 UTCEPSS rescore
  17. 2026-06-28 04:54 UTCEPSS rescore
  18. 2026-06-28 04:54 UTCEPSS rescore
  19. 2026-06-27 03:06 UTCEPSS rescore
  20. 2026-06-25 13:47 UTCEPSS rescore
  21. 2026-06-25 13:47 UTCEPSS rescore
  22. 2026-06-24 14:03 UTCEPSS rescore
  23. 2026-06-24 14:03 UTCEPSS rescore
  24. 2026-06-23 21:31 UTCEPSS rescore
  25. 2026-06-23 21:30 UTCEPSS rescore
Show 46 more
  1. 2026-06-21 14:54 UTCEPSS rescore
  2. 2026-06-21 14:54 UTCEPSS rescore
  3. 2026-06-21 01:57 UTCEPSS rescore
  4. 2026-06-21 01:57 UTCEPSS rescore
  5. 2026-06-19 19:23 UTCEPSS rescore
  6. 2026-06-19 19:23 UTCEPSS rescore
  7. 2026-06-18 17:50 UTCEPSS rescore
  8. 2026-06-17 17:50 UTCEPSS rescore
  9. 2026-06-16 17:50 UTCEPSS rescore
  10. 2026-06-15 17:45 UTCEPSS rescore
  11. 2026-06-14 23:15 UTCEPSS rescore
  12. 2026-06-14 23:15 UTCEPSS rescore
  13. 2026-06-14 12:13 UTCOSV refresh
  14. 2026-06-13 22:58 UTCEPSS rescore
  15. 2026-06-12 23:09 UTCEPSS rescore
  16. 2026-06-11 13:58 UTCEPSS rescore
  17. 2026-06-10 22:16 UTCEPSS rescore
  18. 2026-06-10 13:19 UTCEPSS rescore
  19. 2026-06-08 14:15 UTCEPSS rescore
  20. 2026-06-07 15:23 UTCEPSS rescore
  21. 2026-06-07 15:23 UTCEPSS rescore
  22. 2026-06-05 22:45 UTCEPSS rescore
  23. 2026-06-05 22:45 UTCEPSS rescore
  24. 2026-06-05 06:08 UTCEPSS rescore
  25. 2026-06-05 06:08 UTCEPSS rescore
  26. 2026-06-04 13:10 UTCEPSS rescore
  27. 2026-06-04 13:10 UTCEPSS rescore
  28. 2026-06-02 20:11 UTCEPSS rescore
  29. 2026-06-02 20:11 UTCEPSS rescore
  30. 2026-06-01 13:50 UTCEPSS rescore
  31. 2026-06-01 13:50 UTCEPSS rescore
  32. 2026-05-31 22:29 UTCEPSS rescore
  33. 2026-05-31 22:29 UTCEPSS rescore
  34. 2026-05-31 00:14 UTCEPSS rescore
  35. 2026-05-31 00:14 UTCEPSS rescore
  36. 2026-05-29 13:42 UTCEPSS rescore
  37. 2026-05-28 13:43 UTCEPSS rescore
  38. 2026-05-27 13:38 UTCEPSS rescore
  39. 2026-05-27 10:07 UTCEG score recompute
  40. 2026-05-27 10:07 UTCVendor advisory
  41. 2026-05-26 13:42 UTCEPSS rescore
  42. 2026-05-26 13:42 UTCEPSS rescore
  43. 2026-05-26 07:17 UTCEPSS rescore
  44. 2026-05-26 07:17 UTCEPSS rescore
  45. 2026-05-26 07:17 UTCEPSS rescore
  46. 2026-05-24 22:56 UTCOSV refresh

Frequently asked(5)

What is CVE-2019-16782?
CVE-2019-16782 is a medium vulnerability published on December 18, 2019. 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…
When was CVE-2019-16782 disclosed?
CVE-2019-16782 was first published in the National Vulnerability Database on December 18, 2019, with the most recent update on February 13, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2019-16782 actively exploited?
CVE-2019-16782 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 88.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2019-16782?
CVE-2019-16782 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2019-16782?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2019-16782, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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