Proxy crash via oversized Gopher response
Published Jul 17, 2022 · Updated Aug 4, 2024
Denial of service in Squid 3.x through 3.5.28, 4.x through 4.17, and 5.x before 5.6 allows remote attackers to crash the proxy. The gopherToHTML routine accumulates generated HTML from attacker-controlled Gopher response fields in a size-limited String, where an oversized response triggers an assertion. Exploitation requires Squid to fetch an attacker-controlled Gopher URL permitted by its access rules, and the resulting crash interrupts the proxy without reported data disclosure or modification.
Summary
What happened
Denial of service in Squid 3.x through 3.5.28, 4.x through 4.17, and 5.x before 5.6 allows remote attackers to crash the proxy. The gopherToHTML routine accumulates generated HTML from attacker-controlled Gopher response fields in a size-limited String, where an oversized response triggers an assertion. Exploitation requires Squid to fetch an attacker-controlled Gopher URL permitted by its access rules, and the resulting crash interrupts the proxy without reported data disclosure or modification.
The record
- CVE
- CVE-2021-46784
- Published
- Jul 17, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-617, T1499.004
- Attack vector
- network
- Privileges
- Unavailable
Timeline
How it unfolded
- Jul 17, 2022CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
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Published CVSS scores
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Attacks
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Public exploit references
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Technologies
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