Swiftnio
CVE-2019-9515
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
1DescriptionNVD
Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. The attacker sends a stream of SETTINGS frames to the peer. Since the RFC requires that the peer reply with one acknowledgement per SETTINGS frame, an empty SETTINGS frame is almost equivalent in behavior to a ping. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both.
AnalysisAI
Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. Some HTTP/2 implementations are vulnerable to a settings flood, potentially leading to a denial of service. The attacker sends a stream of SETTINGS frames to the peer. Since the RFC requires that the peer reply with one acknowledgement per SETTINGS frame, an empty SETTINGS frame is almost equivalent in behavior to a ping. Depending on how efficiently this data is queued, this can consume excess CPU, memory, or both. Affected products include: Apple Swiftnio, Apache Traffic Server, Canonical Ubuntu Linux, Debian Debian Linux, Synology Skynas.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.
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Same weakness CWE-400 – Uncontrolled Resource Consumption
View allSame technique Denial Of Service
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External POC / Exploit Code
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