Service hang via zero-length GTP-U extension header
Published Feb 1, 2023 · Updated Mar 27, 2025
Resource exhaustion in Open5GS 2.4.12 and earlier and 2.5.6 and earlier allows remote attackers to hang GTP-U processes. The shared GTP library advances through extension headers using their declared length without rejecting zero, so a zero-length header traps the parser in an infinite loop. Any endpoint accepting GTPv1-U, including UPF, SMF, and SGW-U, can be hung without an existing tunnel by a Supported Extension Headers Notification.
Summary
What happened
Resource exhaustion in Open5GS 2.4.12 and earlier and 2.5.6 and earlier allows remote attackers to hang GTP-U processes. The shared GTP library advances through extension headers using their declared length without rejecting zero, so a zero-length header traps the parser in an infinite loop. Any endpoint accepting GTPv1-U, including UPF, SMF, and SGW-U, can be hung without an existing tunnel by a Supported Extension Headers Notification.
The record
- CVE
- CVE-2023-23846
- Published
- Feb 1, 2023
- Updated
- Mar 27, 2025
- Vendor
- Open5GS
- Product
- Open5GS
- Classifications
- CWE-770, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 1, 2023CVE publishedPublication date reported by the CVE source.
- Mar 27, 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=<= 2.4.12
- Affected versionversion=<= 2.5.6
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
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Your stack
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