Account impersonation via post-logout session token reuse
Published May 13, 2025 · Updated May 13, 2025
Insufficient session expiration in Siemens SIMATIC PCS neo 4.1 and 5.0 allows remote attackers to reuse session tokens after logout. The logout path leaves the server-side session token valid instead of revoking it, so later requests retain the legitimate user's authorization. The gate is prior possession of that token; affected releases permit access and actions within the legitimate user's session after logout.
Summary
What happened
Insufficient session expiration in Siemens SIMATIC PCS neo 4.1 and 5.0 allows remote attackers to reuse session tokens after logout. The logout path leaves the server-side session token valid instead of revoking it, so later requests retain the legitimate user's authorization. The gate is prior possession of that token; affected releases permit access and actions within the legitimate user's session after logout.
The record
- CVE
- CVE-2025-40566
- Published
- May 13, 2025
- Updated
- May 13, 2025
- Vendor
- Siemens
- Product
- SIMATIC PCS neo
- Classifications
- CWE-613, T1550.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 13, 2025CVE publishedPublication date reported by the CVE source.
- May 13, 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 <V4.1 Update 3
- Affected versionversion=0 <V5.0 Update 1
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
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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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