stunnel 4.21 through 4.54, when CONNECT protocol negotiation and NTLM authentication are enabled, does not correctly perform integer conversion, which allows remote proxy servers to execute arbitrary code via a crafted request that triggers a buffer overflow.
CVSS Details
- CVSS 3.1 Base Score: 7
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Centos_linux | — | Upgrade stunnel | Dec 1, 2016 | Mar 8, 2013 |
| Debian | — | Upgrade stunnel4 | Jul 30, 2024 | Mar 8, 2013 |
| Freebsd | — | Upgrade stunnel | Dec 10, 2025 | Mar 3, 2013 |
| Gentoo Linux | — | Upgrade net-misc/stunnel. | Oct 30, 2017 | Mar 8, 2013 |
| Oracle_linux | — | Upgrade stunnel | Oct 16, 2024 | Mar 8, 2013 |
| Suse | — | Upgrade stunnel | Dec 12, 2013 | Mar 8, 2013 |
| Ubuntu | — | Upgrade stunnel4 | Nov 19, 2024 | Mar 8, 2013 |
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