libcurl may read outside of a heap allocated buffer when doing FTP. When libcurl connects to an FTP server and successfully logs in (anonymous or not), it asks the server for the current directory with the `PWD` command. The server then responds with a 257 response containing the path, inside double quotes. The returned path name is then kept by libcurl for subsequent uses. Due to a flaw in the string parser for this directory name, a directory name passed like this but without a closing double quote would lead to libcurl not adding a trailing NUL byte to the buffer holding the name. When libcurl would then later access the string, it could read beyond the allocated heap buffer and crash or wrongly access data beyond the buffer, thinking it was part of the path. A malicious server could abuse this fact and effectively prevent libcurl-based clients to work with it - the PWD command is always issued on new FTP connections and the mistake has a high chance of causing a segfault. The simple fact that this has issue remained undiscovered for this long could suggest that malformed PWD responses are rare in benign servers. We are not aware of any exploit of this flaw. This bug was introduced in commit [415d2e7cb7](https://github.com/curl/curl/commit/415d2e7cb7), March 2005. In libcurl version 7.56.0, the parser always zero terminates the string but also rejects it if not terminated properly with a final double quote.
This vulnerability carries a HIGH severity rating with a CVSS v3.1 score of 7.5, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 1 product from haxx organizations running these solutions should prioritize assessment and patching.
First disclosed in 2017, this vulnerability was reported during a period defined by widespread IoT adoption challenges, mobile security concerns, and the emergence of advanced persistent threat (APT) techniques. Contemporary mitigation strategies focused on secure development practices and third-party component vetting.
2017-10-06T13:29:00.207
2026-06-17T00:58:59.980
Modified
CVSSv3.0: 7.5 (HIGH)
AV:N/AC:L/Au:N/C:N/I:N/A:P
10.0
2.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | haxx | libcurl | 7.7 | Yes |
| Application | haxx | libcurl | 7.7.1 | Yes |
| Application | haxx | libcurl | 7.7.2 | Yes |
| Application | haxx | libcurl | 7.7.3 | Yes |
| Application | haxx | libcurl | 7.8 | Yes |
| Application | haxx | libcurl | 7.8.1 | Yes |
| Application | haxx | libcurl | 7.9 | Yes |
| Application | haxx | libcurl | 7.9.1 | Yes |
| Application | haxx | libcurl | 7.9.2 | Yes |
| Application | haxx | libcurl | 7.9.3 | Yes |
| Application | haxx | libcurl | 7.9.4 | Yes |
| Application | haxx | libcurl | 7.9.5 | Yes |
| Application | haxx | libcurl | 7.9.6 | Yes |
| Application | haxx | libcurl | 7.9.7 | Yes |
| Application | haxx | libcurl | 7.9.8 | Yes |
| Application | haxx | libcurl | 7.10 | Yes |
| Application | haxx | libcurl | 7.10.1 | Yes |
| Application | haxx | libcurl | 7.10.2 | Yes |
| Application | haxx | libcurl | 7.10.3 | Yes |
| Application | haxx | libcurl | 7.10.4 | Yes |
| Application | haxx | libcurl | 7.10.5 | Yes |
| Application | haxx | libcurl | 7.10.6 | Yes |
| Application | haxx | libcurl | 7.10.7 | Yes |
| Application | haxx | libcurl | 7.10.8 | Yes |
| Application | haxx | libcurl | 7.11.0 | Yes |
| Application | haxx | libcurl | 7.11.1 | Yes |
| Application | haxx | libcurl | 7.11.2 | Yes |
| Application | haxx | libcurl | 7.12.0 | Yes |
| Application | haxx | libcurl | 7.12.1 | Yes |
| Application | haxx | libcurl | 7.12.2 | Yes |
| Application | haxx | libcurl | 7.12.3 | Yes |
| Application | haxx | libcurl | 7.13.0 | Yes |
| Application | haxx | libcurl | 7.13.1 | Yes |
| Application | haxx | libcurl | 7.13.2 | Yes |
| Application | haxx | libcurl | 7.14.0 | Yes |
| Application | haxx | libcurl | 7.14.1 | Yes |
| Application | haxx | libcurl | 7.15.0 | Yes |
| Application | haxx | libcurl | 7.15.1 | Yes |
| Application | haxx | libcurl | 7.15.2 | Yes |
| Application | haxx | libcurl | 7.15.3 | Yes |
| Application | haxx | libcurl | 7.15.4 | Yes |
| Application | haxx | libcurl | 7.15.5 | Yes |
| Application | haxx | libcurl | 7.16.0 | Yes |
| Application | haxx | libcurl | 7.16.1 | Yes |
| Application | haxx | libcurl | 7.16.2 | Yes |
| Application | haxx | libcurl | 7.16.3 | Yes |
| Application | haxx | libcurl | 7.16.4 | Yes |
| Application | haxx | libcurl | 7.17.0 | Yes |
| Application | haxx | libcurl | 7.17.1 | Yes |
| Application | haxx | libcurl | 7.18.0 | Yes |
| Application | haxx | libcurl | 7.18.1 | Yes |
| Application | haxx | libcurl | 7.18.2 | Yes |
| Application | haxx | libcurl | 7.19.0 | Yes |
| Application | haxx | libcurl | 7.19.1 | Yes |
| Application | haxx | libcurl | 7.19.2 | Yes |
| Application | haxx | libcurl | 7.19.3 | Yes |
| Application | haxx | libcurl | 7.19.4 | Yes |
| Application | haxx | libcurl | 7.19.5 | Yes |
| Application | haxx | libcurl | 7.19.6 | Yes |
| Application | haxx | libcurl | 7.19.7 | Yes |
| Application | haxx | libcurl | 7.20.0 | Yes |
| Application | haxx | libcurl | 7.20.1 | Yes |
| Application | haxx | libcurl | 7.21.0 | Yes |
| Application | haxx | libcurl | 7.21.1 | Yes |
| Application | haxx | libcurl | 7.21.2 | Yes |
| Application | haxx | libcurl | 7.21.3 | Yes |
| Application | haxx | libcurl | 7.21.4 | Yes |
| Application | haxx | libcurl | 7.21.5 | Yes |
| Application | haxx | libcurl | 7.21.6 | Yes |
| Application | haxx | libcurl | 7.21.7 | Yes |
| Application | haxx | libcurl | 7.22.0 | Yes |
| Application | haxx | libcurl | 7.23.0 | Yes |
| Application | haxx | libcurl | 7.23.1 | Yes |
| Application | haxx | libcurl | 7.24.0 | Yes |
| Application | haxx | libcurl | 7.25.0 | Yes |
| Application | haxx | libcurl | 7.26.0 | Yes |
| Application | haxx | libcurl | 7.27.0 | Yes |
| Application | haxx | libcurl | 7.28.0 | Yes |
| Application | haxx | libcurl | 7.28.1 | Yes |
| Application | haxx | libcurl | 7.29.0 | Yes |
| Application | haxx | libcurl | 7.30.0 | Yes |
| Application | haxx | libcurl | 7.31.0 | Yes |
| Application | haxx | libcurl | 7.32.0 | Yes |
| Application | haxx | libcurl | 7.33.0 | Yes |
| Application | haxx | libcurl | 7.34.0 | Yes |
| Application | haxx | libcurl | 7.35.0 | Yes |
| Application | haxx | libcurl | 7.36.0 | Yes |
| Application | haxx | libcurl | 7.37.0 | Yes |
| Application | haxx | libcurl | 7.37.1 | Yes |
| Application | haxx | libcurl | 7.38.0 | Yes |
| Application | haxx | libcurl | 7.39 | Yes |
| Application | haxx | libcurl | 7.40.0 | Yes |
| Application | haxx | libcurl | 7.41.0 | Yes |
| Application | haxx | libcurl | 7.42.0 | Yes |
| Application | haxx | libcurl | 7.42.1 | Yes |
| Application | haxx | libcurl | 7.43.0 | Yes |
| Application | haxx | libcurl | 7.44.0 | Yes |
| Application | haxx | libcurl | 7.45.0 | Yes |
| Application | haxx | libcurl | 7.46.0 | Yes |
| Application | haxx | libcurl | 7.47.0 | Yes |
| Application | haxx | libcurl | 7.47.1 | Yes |
| Application | haxx | libcurl | 7.48.0 | Yes |
| Application | haxx | libcurl | 7.49.0 | Yes |
| Application | haxx | libcurl | 7.49.1 | Yes |
| Application | haxx | libcurl | 7.50.0 | Yes |
| Application | haxx | libcurl | 7.50.1 | Yes |
| Application | haxx | libcurl | 7.50.2 | Yes |
| Application | haxx | libcurl | 7.50.3 | Yes |
| Application | haxx | libcurl | 7.51.0 | Yes |
| Application | haxx | libcurl | 7.52.0 | Yes |
| Application | haxx | libcurl | 7.52.1 | Yes |
| Application | haxx | libcurl | 7.53.0 | Yes |
| Application | haxx | libcurl | 7.53.1 | Yes |
| Application | haxx | libcurl | 7.54.0 | Yes |
| Application | haxx | libcurl | 7.54.1 | Yes |
| Application | haxx | libcurl | 7.55.0 | Yes |
| Application | haxx | libcurl | 7.55.1 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For haxx's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.