Authentication delay via block-for logic error
Published Aug 25, 2021 · Updated Nov 7, 2024
Denial of service in Cisco NX-OS Software allows remote attackers to restart the AAA daemon through brute-force login attempts. When the nondefault system login block-for command detects and acts on repeated failures, a logic error causes an out-of-bounds write that crashes the login process. The command is disabled by default; exploitation delays device authentication, and the reported consequence is limited to service interruption.
Summary
What happened
Denial of service in Cisco NX-OS Software allows remote attackers to restart the AAA daemon through brute-force login attempts. When the nondefault system login block-for command detects and acts on repeated failures, a logic error causes an out-of-bounds write that crashes the login process. The command is disabled by default; exploitation delays device authentication, and the reported consequence is limited to service interruption.
The record
- CVE
- CVE-2021-1590
- Published
- Aug 25, 2021
- Updated
- Nov 7, 2024
- Vendor
- ClamAV
- Product
- Cisco NX-OS Software
- Classifications
- CWE-787, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 25, 2021CVE publishedPublication date reported by the CVE source.
- Nov 7, 2024Record updatedLatest update available in the CVE record.
Exploitability
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- Affected versionversion=n/a
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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Public exploit references
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Technologies
Your stack
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Your stack
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