Unauthenticated service interruption via TLS renegotiation
Published Aug 10, 2022 · Updated Apr 14, 2026
Resource exhaustion in Siemens SCALANCE and RUGGEDCOM firmware allows unauthenticated remote attackers to interrupt service. The TLS endpoint mishandles repeated SSL/TLS parameter renegotiation, allowing requests to bypass TCP brute-force prevention and consume unthrottled resources. Network reachability to the TLS service is sufficient, and the interruption lasts for the duration of the attack.
Summary
What happened
Resource exhaustion in Siemens SCALANCE and RUGGEDCOM firmware allows unauthenticated remote attackers to interrupt service. The TLS endpoint mishandles repeated SSL/TLS parameter renegotiation, allowing requests to bypass TCP brute-force prevention and consume unthrottled resources. Network reachability to the TLS service is sufficient, and the interruption lasts for the duration of the attack.
The record
- CVE
- CVE-2022-36324
- Published
- Aug 10, 2022
- Updated
- Apr 14, 2026
- Vendor
- Siemens
- Product
- SCALANCE XR328-4C WG (24xFE, 4xGE, DC24V)
- Classifications
- CWE-770, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 10, 2022CVE publishedPublication date reported by the CVE source.
- Apr 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <V4.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo