The URL percent-encoding decode function in libcurl before 7.51.0 is called `curl_easy_unescape`. Internally, even if this function would be made to allocate a unscape destination buffer larger than 2GB, it would return that new length in a signed 32 bit integer variable, thus the length would get either just truncated or both truncated and turned negative. That could then lead to libcurl writing outside of its heap based buffer.
CVSS Details
- CVSS 3.1 Base Score: 9.8
- CVSS 3.0 Base Score: 3.7
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | — | Upgrade curl | Jul 31, 2018 | Jul 31, 2018 |
| Amazon_linux | — | Upgrade curl | Nov 11, 2016 | Nov 2, 2016 |
| Apple Osx Curl | — | Upgrade macOS to the latest version | Dec 16, 2016 | Dec 16, 2016 |
| Arch Linux | — | Upgrade to the latest version of Arch Linux | Jul 11, 2025 | Jul 31, 2018 |
| Debian | — | Upgrade curl | Nov 4, 2016 | Nov 2, 2016 |
| Freebsd | — | Upgrade curl | Nov 14, 2016 | Nov 2, 2016 |
| Gentoo Linux | — | Upgrade net-misc/curl. | Oct 30, 2017 | Jan 19, 2017 |
| Huawei Euleros 2_0_sp1 | — | Upgrade libcurlUpgrade libcurl-develUpgrade curl | Aug 28, 2019 | Jul 31, 2018 |
| Huawei Euleros 2_0_sp2 | — | Upgrade libcurlUpgrade curlUpgrade libcurl-devel | Aug 28, 2019 | Jul 31, 2018 |
| Oracle Solaris | — | Upgrade web/curl to version 7.45.0-0.175.3.18.0.1.0 on Solaris 11.3 | May 29, 2017 | May 29, 2017 |
| Oracle_linux | — | Upgrade libcurl-develUpgrade libcurlUpgrade curl | May 22, 2019 | Nov 2, 2016 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Jul 31, 2018 |
| Suse | — | Upgrade libcurl4-openssl1-x86Upgrade libcurl4-openssl1-32bitUpgrade libcurl4-openssl1Upgrade libcurl4-32bitUpgrade curlUpgrade curl-openssl1Upgrade sles12sp1-docker-imageUpgrade sles12-docker-imageUpgrade libcurl4Upgrade libcurl4-x86Upgrade libcurl-devel | Nov 3, 2016 | Nov 2, 2016 |
| Ubuntu | — | Upgrade libcurl3-gnutlsUpgrade libcurl3-nssUpgrade libcurl3 | Nov 3, 2016 | Nov 2, 2016 |
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