When libcurl is asked to perform automatic gzip decompression of content-encoded HTTP responses with the `CURLOPT_ACCEPT_ENCODING` option, **using zlib 1.2.0.3 or older**, an attacker-controlled integer overflow would make libcurl perform a buffer overflow.
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.
| Link | Tags |
|---|---|
| https://curl.se/docs/CVE-2025-0725.json | vendor advisory |
| https://curl.se/docs/CVE-2025-0725.html | vendor advisory |
| https://hackerone.com/reports/2956023 | issue tracking exploit |
| http://www.openwall.com/lists/oss-security/2025/02/05/3 | mailing list |
| http://www.openwall.com/lists/oss-security/2025/02/06/2 | mailing list |
| http://www.openwall.com/lists/oss-security/2025/02/06/4 | mailing list |
| https://github.com/curl/curl/commit/76f83f0db23846e254d940ec7 | patch |
| https://security.netapp.com/advisory/ntap-20250306-0009/ | third party advisory |