CVE-2023-44487
The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
HTTP/2 Rapid Reset Attack Vulnerability
IETF HTTP/2
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
10/10/2023
This vulnerability affects a common open-source component, third-party library, or protocol used by different products. For more information, please see: HTTP/2 Rapid Reset Vulnerability, CVE-2023-44487 | CISA: https://www.cisa.gov/news-events/alerts/2023/10/10/http2-rapid-reset-vulnerability-cve-2023-44487; https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/; https://nvd.nist.gov/vuln/detail/CVE-2023-44487
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score (Exploitation Probability)
This vulnerability has a 94.40% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.
CWE Classification
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