CVE-2023-44487
CVE-2023-44487 is a high-severity vulnerability in Siemens Sinec Ins with a CVSS 3.x base score of 7.5. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-10-10). The underlying weakness is classified as CWE-400.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 100% (100th percentile)
- Actively exploited: Yes — listed in CISA KEV (added 2023-10-10)
- EU (EUVD) id: EUVD-2023-2795
- EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-10-10)
- Weakness: CWE-400
- Affected product: Siemens Sinec Ins
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2023-44487?
- CVE-2023-44487 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2023-44487 being actively exploited?
- Yes. CVE-2023-44487 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-10-10, which means active exploitation has been confirmed. It should be prioritised for remediation.
- What products are affected by CVE-2023-44487?
- CVE-2023-44487 primarily affects Siemens Sinec Ins. In total, 227 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-44487?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
- Does CVE-2023-44487 have an EU (EUVD) identifier?
- Yes. CVE-2023-44487 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-2795. It is also flagged as exploited in the EUVD (since 2023-10-10).
- When was CVE-2023-44487 published?
- CVE-2023-44487 was published on 2023-10-10 and last updated on 2026-06-17.
References
- http://www.openwall.com/lists/oss-security/2023/10/10/6
- http://www.openwall.com/lists/oss-security/2023/10/10/7
- http://www.openwall.com/lists/oss-security/2023/10/13/4
- http://www.openwall.com/lists/oss-security/2023/10/13/9
- http://www.openwall.com/lists/oss-security/2023/10/18/4
- http://www.openwall.com/lists/oss-security/2023/10/18/8
- http://www.openwall.com/lists/oss-security/2023/10/19/6
- http://www.openwall.com/lists/oss-security/2023/10/20/8
- https://access.redhat.com/security/cve/cve-2023-44487
- https://arstechnica.com/security/2023/10/how-ddosers-used-the-http-2-protocol-to-deliver-attacks-of-unprecedented-size/
- https://aws.amazon.com/security/security-bulletins/AWS-2023-011/
- https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/
- https://blog.cloudflare.com/zero-day-rapid-reset-http2-record-breaking-ddos-attack/
- https://blog.litespeedtech.com/2023/10/11/rapid-reset-http-2-vulnerablilty/
- https://blog.qualys.com/vulnerabilities-threat-research/2023/10/10/cve-2023-44487-http-2-rapid-reset-attack
- https://blog.vespa.ai/cve-2023-44487/
- https://bugzilla.proxmox.com/show_bug.cgi?id=4988
- https://bugzilla.redhat.com/show_bug.cgi?id=2242803
- https://bugzilla.suse.com/show_bug.cgi?id=1216123
- https://cgit.freebsd.org/ports/commit/?id=c64c329c2c1752f46b73e3e6ce9f4329be6629f9
- https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/
- https://cloud.google.com/blog/products/identity-security/how-it-works-the-novel-http2-rapid-reset-ddos-attack
- https://community.traefik.io/t/is-traefik-vulnerable-to-cve-2023-44487/20125
- https://discuss.hashicorp.com/t/hcsec-2023-32-vault-consul-and-boundary-affected-by-http-2-rapid-reset-denial-of-service-vulnerability-cve-2023-44487/59715
- https://edg.io/lp/blog/resets-leaks-ddos-and-the-tale-of-a-hidden-cve
- https://forums.swift.org/t/swift-nio-http2-security-update-cve-2023-44487-http-2-dos/67764
- https://gist.github.com/adulau/7c2bfb8e9cdbe4b35a5e131c66a0c088
- https://github.com/Azure/AKS/issues/3947
- https://github.com/Kong/kong/discussions/11741
- https://github.com/advisories/GHSA-qppj-fm5r-hxr3
Affected products (227)
- cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518f-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:*:*:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:1.0:-:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:1.0:sp1:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:1.0:sp2:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:1.0:sp2_update_1:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_ins:1.0:sp2_update_2:*:*:*:*:*:*
- cpe:2.3:a:siemens:sinec_nms:*:*:*:*:*:*:*:*
- cpe:2.3:a:siemens:st7_scadaconnect:*:*:*:*:*:*:*:*
- cpe:2.3:o:siemens:ruggedcom_ape1808_firmware:-:*:*:*:*:*:*:*
- cpe:2.3:o:siemens:simatic_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:siemens:siplus_s7-1500_cpu_1518-4_pn\/dp_mfp_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:a:ietf:http:2.0:*:*:*:*:*:*:*
- cpe:2.3:a:nghttp2:nghttp2:*:*:*:*:*:*:*:*
- cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.24.10:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.25.9:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.26.4:*:*:*:*:*:*:*
- cpe:2.3:a:envoyproxy:envoy:1.27.0:*:*:*:*:*:*:*
- cpe:2.3:a:eclipse:jetty:*:*:*:*:*:*:*:*
- cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:*
- cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*
- cpe:2.3:a:golang:http2:*:*:*:*:*:go:*:*
- cpe:2.3:a:golang:networking:*:*:*:*:*:go:*:*
- cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_access_policy_manager:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_advanced_firewall_manager:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_advanced_web_application_firewall:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_advanced_web_application_firewall:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_analytics:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_acceleration_manager:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_security_manager:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_visibility_and_reporting:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_visibility_and_reporting:17.1.0:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_carrier-grade_nat:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_carrier-grade_nat:17.1.0:*:*:*:*:*:*:*
More vulnerabilities in Siemens Sinec Ins
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- CVE-2024-46890 — Critical (CVSS 9.1): A vulnerability has been identified in SINEC INS (All versions < V1.0 SP2 Update 3). The affected application does not…
- CVE-2022-35255 — Critical (CVSS 9.1): A weak randomness in WebCrypto keygen vulnerability exists in Node.js 18 due to a change with EntropySource() in…
- CVE-2021-22945 — Critical (CVSS 9.1): When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a…
- CVE-2026-46748 — High (CVSS 8.8): A vulnerability has been identified in SINEC INS (All versions < V1.0 SP2 Update 6). The affected system includes a…
All CVEs affecting Siemens Sinec Ins →
Other CWE-400 (Uncontrolled Resource Consumption) vulnerabilities
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- CVE-2025-43193 — Critical (CVSS 9.8): The issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.6, macOS Sonoma 14.7.7,…
- CVE-2025-24269 — Critical (CVSS 9.8): The issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.4. An app may be able to…
- CVE-2025-24264 — Critical (CVSS 9.8): The issue was addressed with improved memory handling. This issue is fixed in Safari 18.4, iOS 18.4 and iPadOS 18.4,…
- CVE-2025-24260 — Critical (CVSS 9.8): The issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.4, macOS Sonoma 14.7.5,…
Browse all CWE-400 (Uncontrolled Resource Consumption) vulnerabilities →
Threat intelligence
Threat-intel indicators referencing this CVE:
- 196.188.93.169 (ipv4-addr)
- 114.67.252.10 (ipv4-addr)
- 134.209.202.49 (ipv4-addr)
- 180.93.138.150 (ipv4-addr)
- 5.182.26.69 (ipv4-addr)
- 45.67.217.113 (ipv4-addr)
- 115.190.154.102 (ipv4-addr)
- 101.126.145.214 (ipv4-addr)