TCP connection hijacking via predictable sequence numbers
Published Oct 10, 2023 · Updated Sep 19, 2024
Weak TCP ISN generation in Butok FNET 4.6.3 allows remote attackers to hijack or spoof TCP connections via predictable sequence numbers. The TCP stack initializes its ISN generator with a constant and advances it by constant increments instead of producing unpredictable values. Exploitation requires network access to an active FNET TCP service and enables data injection, connection spoofing, or interruption of the targeted connection.
Summary
What happened
Weak TCP ISN generation in Butok FNET 4.6.3 allows remote attackers to hijack or spoof TCP connections via predictable sequence numbers. The TCP stack initializes its ISN generator with a constant and advances it by constant increments instead of producing unpredictable values. Exploitation requires network access to an active FNET TCP service and enables data injection, connection spoofing, or interruption of the targeted connection.
The record
- CVE
- CVE-2020-27633
- Published
- Oct 10, 2023
- Updated
- Sep 19, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-330, T1565.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 10, 2023CVE publishedPublication date reported by the CVE source.
- Sep 19, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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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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