Session hijacking via predictable rand-seeded identifiers
Published May 11, 2026 · Updated May 11, 2026
Predictable session identifiers in ASPEER WebDyne::Session 2.075 and earlier allow remote attackers to hijack authenticated sessions. The handler hashes Perl's predictable 32-bit rand() output with MD5; PID, time, and object-address values only bound rand() and add no entropy. Exploitation requires predicting a live identifier and presenting it as the session cookie, which grants that session's existing privileges without interrupting service.
Summary
What happened
Predictable session identifiers in ASPEER WebDyne::Session 2.075 and earlier allow remote attackers to hijack authenticated sessions. The handler hashes Perl's predictable 32-bit rand() output with MD5; PID, time, and object-address values only bound rand() and add no entropy. Exploitation requires predicting a live identifier and presenting it as the session cookie, which grants that session's existing privileges without interrupting service.
The record
- CVE
- CVE-2026-5084
- Published
- May 11, 2026
- Updated
- May 11, 2026
- Vendor
- ASPEER
- Product
- WebDyne::Session
- Classifications
- T1550.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 11, 2026CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record 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 <=2.075
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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