A peer could send empty handshake fragments containing only padding which would be kept in memory until a full handshake was received, resulting in memory exhaustion. This issue affects versions v2019.01.28.00 and above of fizz, until v2019.08.05.00.
Conclusion & alert: CVE-2019-11924 is rated Moderate Risk (54.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.65%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-05 | 0.66% | 0.65% | -0.01% |
| 2 | 2026-01-26 | 0.51% | 0.66% | +0.15% |
| 3 | 2025-03-30 | — | 0.51% | — |
Full EPSS history (11 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.0 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 7.8 | 2.0 | HIGH |
|
10.0 | 6.9 | [email protected] |
| URL | Tags |
|---|---|
| https://github.com/facebookincubator/fizz/commit/3eaddb33619eaaf74a760872850c550ad8f5c52f | Patch Third Party Advisory |
| https://github.com/facebookincubator/fizz/commit/6bf67137ef1ee5cd70c842b014c322b7deaf994b | Patch Third Party Advisory |
| https://www.facebook.com/security/advisories/cve-2019-11924 | Vendor Advisory |