CVE-2026-92389
TFTP direction confusion
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.
INFO
Published Date :
Oct. 20, 2026, 9:17 p.m.
Last Modified :
Oct. 20, 2026, 9:17 p.m.
Remotely Exploit :
No
Source :
2499f714-1537-4658-8207-48ae4bb9eae9
Solution
- Update libcurl to the latest version.
- Apply security patches provided by the vendor.
- Validate TFTP server configurations.
- Avoid handle reuse for different protocols.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-92389.
| URL | Resource |
|---|---|
| https://curl.se/docs/CVE-2026-92389.html | |
| https://curl.se/docs/CVE-2026-92389.json | |
| https://hackerone.com/reports/4022568 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-92389 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-92389
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-92389 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-92389 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 2499f714-1537-4658-8207-48ae4bb9eae9
Oct. 20, 2026
Action Type Old Value New Value Added 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. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/92xxx/CVE-2026-92389.json">CVE-2026-92389</a> Added Reference https://curl.se/docs/CVE-2026-92389.html Added Reference https://curl.se/docs/CVE-2026-92389.json Added Reference https://hackerone.com/reports/4022568