Credential replay and code execution via nonce overflow
Published Apr 23, 2020 · Updated Aug 4, 2024
Integer overflow in HTTP Digest authentication in Squid 2.5 through 5.0.1 allows remote attackers to replay nonces or execute code. The authDigestNonceLink function increments a signed short reference counter until it wraps, enabling a nonce to be freed while a request still uses it. Digest authentication must be enabled; memory pooling permits access with a sniffed nonce, while disabling pooling exposes remote code execution.
Summary
What happened
Integer overflow in HTTP Digest authentication in Squid 2.5 through 5.0.1 allows remote attackers to replay nonces or execute code. The authDigestNonceLink function increments a signed short reference counter until it wraps, enabling a nonce to be freed while a request still uses it. Digest authentication must be enabled; memory pooling permits access with a sniffed nonce, while disabling pooling exposes remote code execution.
The record
- CVE
- CVE-2020-11945
- Published
- Apr 23, 2020
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 23, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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