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Findings

CVE-2023-44487

HTTP/2 Rapid Reset Attack Vulnerability

Published Oct 10, 2023 · updated Aug 11, 2026 · siemens simatic s7-1500 cpu 1518f-4 pn/dp mfp firmware

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.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 10, 2023 · Catalog

    Detected

    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.

  2. Oct 10, 2023 · CISA KEV

    Known exploited

    Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

  3. Oct 31, 2023 · CISA KEV

    Remediation due

    Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

  4. Aug 11, 2026 · Catalog

    Updated

    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.

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.

CISA due date Oct 31, 2023

Affected

  • cpe ietf/http2.0
  • cpe siemens/ruggedcom ape1808 firmwareversion unspecified
  • cpe siemens/simatic s7-1500 cpu 1518-4 pn/dp mfp firmwareversion unspecified
  • cpe siemens/simatic s7-1500 cpu 1518f-4 pn/dp mfp firmwareversion unspecified
  • cpe siemens/sinec insversion unspecified
  • cpe siemens/sinec ins1.0
  • cpe siemens/sinec nmsversion unspecified
  • cpe siemens/siplus s7-1500 cpu 1518-4 pn/dp mfp firmwareversion unspecified
  • vendor IETF HTTP/2version unspecified

Sources

  • CISA KEVCVE-2023-44487

    HTTP/2 contains a rapid reset vulnerability that allows for a distributed denial-of-service attack (DDoS).

    cisa.gov
  • CVE.orgCVE-2023-44487

    Official CVE identifier

    cve.org
  • FIRST EPSSCVE-2023-44487

    30-day exploitation probability 100.0%

    first.org
  • Exploit Database52426

    Public archive entry. The exploit body is not stored here.

    exploit-db.com
  • NIST NVDCVE-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.

    nvd.nist.gov

References