Description
libcurl's TFTP state machine fails to validate state transitions against the requested transfer direction, accepting opening server responses for both reads and writes interchangeably. A malicious TFTP server can respond to a download request in a way that forces the client into transmit mode, prompting libcurl to consume and transmit data from the handle's persistent `CURLOPT_READDATA` pointer - including data remaining from unrelated prior operations, such as an HTTP POST request executed on a reused handle.
Metrics
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HWeakness enumeration
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| curl | curl | >= 8.22.0, <= 8.22.0; >= 8.21.0, <= 8.21.0; >= 8.20.0, <= 8.20.0; >= 8.19.0, <= 8.19.0; >= 8.18.0, <= 8.18.0; >= 8.17.0, <= 8.17.0; >= 8.16.0, <= 8.16.0; >= 8.15.0, <= 8.15.0; >= 8.14.1, <= 8.14.1; >= 8.14.0, <= 8.14.0; >= 8.13.0, <= 8.13.0; >= 8.12.1, <= 8.12.1; >= 8.12.0, <= 8.12.0; >= 8.11.1, <= 8.11.1; >= 8.11.0, <= 8.11.0; >= 8.10.1, <= 8.10.1; >= 8.10.0, <= 8.10.0; >= 8.9.1, <= 8.9.1; >= 8.9.0, <= 8.9.0; >= 8.8.0, <= 8.8.0 |
References
Timeline
- Published
- Oct 20, 2026
- Last modified
- Oct 30, 2026
- NVD status
- Awaiting Analysis