CVE-2023-44487
HTTP/2 Rapid Reset Attack Vulnerability
IN CISA KEV
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.
- Vendor
- IETF
- Product
- HTTP/2
- CVSS 3.1
- 7.5 (high), scored by NVD (primary)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 3.1
- 7.5 (high), scored by 134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CWE
- CWE-400
- Published
- 2023-10-10
- NVD modified
- 2026-08-11
- NVD status
- Analyzed
CISA KEV
- Date added
- 2023-10-10
- Due date
- 2023-10-31
- Ransomware use
- Unknown
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
EPSS
100% chance of exploitation in the next 30 days (percentile 99th)
FIRST EPSS, updated 17 Oct 2026. About EPSS
CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.
References
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- www.openwall.com (Mailing List, Third Party Advisory)
- access.redhat.com (Vendor Advisory)
- arstechnica.com (Press/Media Coverage, Third Party Advisory)
- aws.amazon.com (Third Party Advisory)
- blog.cloudflare.com (Technical Description, Vendor Advisory)
Data last updated 18 Oct 2026. Sources: NVD API 2.0, CISA KEV catalog, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.