Memory disclosure via unterminated ICP URLs
Published Mar 26, 2026 · Updated Mar 26, 2026
Out-of-bounds reads in Squid before 7.5 allow remote attackers to disclose small memory fragments through malformed ICP requests. The ICP v2 and v3 handlers passed a URL pointer from the UDP packet to consumers without verifying that the packet contained a complete, NUL-terminated URL or rejecting embedded NULs and trailing bytes. Only deployments with a nonzero icp_port are exposed, and invalid requests can make error responses return sensitive process memory even when icp_access denies ICP queries.
Summary
What happened
Out-of-bounds reads in Squid before 7.5 allow remote attackers to disclose small memory fragments through malformed ICP requests. The ICP v2 and v3 handlers passed a URL pointer from the UDP packet to consumers without verifying that the packet contained a complete, NUL-terminated URL or rejecting embedded NULs and trailing bytes. Only deployments with a nonzero icp_port are exposed, and invalid requests can make error responses return sensitive process memory even when icp_access denies ICP queries.
The record
- CVE
- CVE-2026-33515
- Published
- Mar 26, 2026
- Updated
- Mar 26, 2026
- Vendor
- The Squid Software Foundation
- Product
- Squid
- Classifications
- CWE-1289, CWE-125
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 26, 2026CVE publishedPublication date reported by the CVE source.
- Mar 26, 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?
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- Affected versionversion=< 7.5
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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