Private-key disclosure via observable timing differences
Published Mar 8, 2022 · Updated Aug 12, 2025
Observable timing discrepancy in Siemens RUGGEDCOM ROS devices allows remote attackers to retrieve encryption private keys. Siemens identifies a third-party component whose private-key operation exposes measurable timing differences, but does not name the component or operation. Network access and no authentication are required; the published impact is disclosure of sensitive key material.
Summary
What happened
Observable timing discrepancy in Siemens RUGGEDCOM ROS devices allows remote attackers to retrieve encryption private keys. Siemens identifies a third-party component whose private-key operation exposes measurable timing differences, but does not name the component or operation. Network access and no authentication are required; the published impact is disclosure of sensitive key material.
The record
- CVE
- CVE-2021-42016
- Published
- Mar 8, 2022
- Updated
- Aug 12, 2025
- Vendor
- Siemens
- Product
- RUGGEDCOM RSG2288
- Classifications
- CWE-208, T1552.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 8, 2022CVE publishedPublication date reported by the CVE source.
- Aug 12, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <V4.3.8
- Affected versionversion=0 <V5.6.0
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.
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Technologies
Your stack
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Your stack
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