Proxy-wide denial of service via oversized nonce-count
Published Nov 3, 2023 · Updated Aug 7, 2026
Stack buffer overflow in Squid 3.2.0.1 through 6.3 allows remote attackers to crash the proxy through HTTP Digest authentication. Auth::Digest::Config::decode passed every nc value to xstrncpy with value.size()+1 even after logging lengths other than eight bytes. Reachability requires HTTP Digest authentication, and exploitation interrupts service for all proxy users on systems with memory protections.
Summary
What happened
Stack buffer overflow in Squid 3.2.0.1 through 6.3 allows remote attackers to crash the proxy through HTTP Digest authentication. Auth::Digest::Config::decode passed every nc value to xstrncpy with value.size()+1 even after logging lengths other than eight bytes. Reachability requires HTTP Digest authentication, and exploitation interrupts service for all proxy users on systems with memory protections.
The record
- CVE
- CVE-2023-46847
- Published
- Nov 3, 2023
- Updated
- Aug 7, 2026
- Vendor
- Red Hat
- Product
- Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
- Classifications
- CWE-120, CWE-122, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 3, 2023CVE publishedPublication date reported by the CVE source.
- Aug 7, 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?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
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
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Technologies
Your stack
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Your stack
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