Authenticated denial of service via CGI buffer overflow
Published Jun 5, 2023 · Updated Jan 8, 2025
Buffer overflow in the CGI program of Zyxel NR7101 Firmware before 1.00(ABUV.8)C0 allows remote authenticated users to interrupt service. The CGI program copies data from a crafted HTTP request into a buffer without adequately checking its size, although Zyxel has not identified the affected endpoint or field. Access to the authenticated web interface is required, and exploitation has no reported data-disclosure or data-modification impact.
Summary
What happened
Buffer overflow in the CGI program of Zyxel NR7101 Firmware before 1.00(ABUV.8)C0 allows remote authenticated users to interrupt service. The CGI program copies data from a crafted HTTP request into a buffer without adequately checking its size, although Zyxel has not identified the affected endpoint or field. Access to the authenticated web interface is required, and exploitation has no reported data-disclosure or data-modification impact.
The record
- CVE
- CVE-2023-27989
- Published
- Jun 5, 2023
- Updated
- Jan 8, 2025
- Vendor
- Zyxel Networks
- Product
- NR7101 Firmware
- Classifications
- CWE-120, T1499
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 5, 2023CVE publishedPublication date reported by the CVE source.
- Jan 8, 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=< V1.00(ABUV.8)C0
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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