CVE-2025-10966

Published Nov 7, 2025

Last updated 3 months ago

CVSS medium 4.3

Overview

Description
curl's code for managing SSH connections when SFTP was done using the wolfSSH powered backend was flawed and missed host verification mechanisms. This prevents curl from detecting MITM attackers and more.
Source
2499f714-1537-4658-8207-48ae4bb9eae9
NVD status
Analyzed
Products
curl

Risk scores

CVSS 3.1

Type
Secondary
Base score
4.3
Impact score
1.4
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

  1. 🚨 New MEDIUM CVE detected in AWS Lambda 🚨 CVE-2025-10966 impacts curl in 14 Lambda base images. Details: https://t.co/YEdpd3SVED More: https://t.co/6EUGaPyRZk #AWS #Lambda #CVE #CloudSecurity #Serverless

    @LambdaWatchdog

    20 Feb 2026

    31 Impressions

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  2. CVE-2025-10966 curl's code for managing SSH connections when SFTP was done using the wolfSSH powered backend was flawed and missed host verification mechanisms. This prevents curl … https://t.co/fbVP7KC2H9

    @CVEnew

    7 Nov 2025

    341 Impressions

    0 Retweets

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  3. CVE-2025-10966: curl: missing SFTP host verification with wolfSSH https://t.co/jwNnfR9hZL managing SSH connections when SFTP was done using the wolfSSH powered backend was flawed and missed host verification mechanisms. This prevents curl from detecting MITM attackers and more.

    @oss_security

    7 Nov 2025

    304 Impressions

    0 Retweets

    1 Like

    0 Bookmarks

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  4. CVE-2025-10966: missing SFTP host verification with wolfSSH https://t.co/MZoZeiZ6x8 #bugbounty #bugbountytips #bugbountytip

    @bountywriteups

    5 Nov 2025

    808 Impressions

    0 Retweets

    4 Likes

    1 Bookmark

    0 Replies

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  5. cURL 8.17.0 is out today to fix the CVE-2025-10966 #security vulnerability, and also add a notifications API to the multi interface, a --knownhosts to the command line tool, and Apple SecTrust support https://t.co/wRMZNCKJUe #OpenSource #Linux

    @9to5linux

    5 Nov 2025

    2237 Impressions

    8 Retweets

    29 Likes

    1 Bookmark

    0 Replies

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Configurations

Related CVEs

  1. When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.•CVE-2026-3805
  2. curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a server, even if the new request uses different credentials for the HTTP proxy. The proper behavior is to create or use a separate connection.•CVE-2026-3784
  3. When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect to a second URL, curl could leak that token to the second hostname under some circumstances. If the hostname that the first request is redirected to has information in the used .netrc file, with either of the `machine` or `default` keywords, curl would pass on the bearer token set for the first host also to the second one.•CVE-2026-3783
  4. libcurl can in some circumstances reuse the wrong connection when asked to do an Negotiate-authenticated HTTP or HTTPS request. libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criterion must first be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different credentials. One underlying reason being that Negotiate sometimes authenticates *connections* and not *requests*, contrary to how HTTP is designed to work. An application that allows Negotiate authentication to a server (that responds wanting Negotiate) with `user1:password1` and then does another operation to the same server also using Negotiate but with `user2:password2` (while the previous connection is still alive) - the second request wrongly reused the same connection and since it then sees that the Negotiate negotiation is already made, it just sends the request over that connection thinking it uses the user2 credentials when it is in fact still using the connection authenticated for user1... The set of authentication methods to use is set with `CURLOPT_HTTPAUTH`. Applications can disable libcurl's reuse of connections and thus mitigate this problem, by using one of the following libcurl options to alter how connections are or are not reused: `CURLOPT_FRESH_CONNECT`, `CURLOPT_MAXCONNECTS` and `CURLMOPT_MAX_HOST_CONNECTIONS` (if using the curl_multi API).•CVE-2026-1965
  5. When doing SSH-based transfers using either SCP or SFTP, and asked to do public key authentication, curl would wrongly still ask and authenticate using a locally running SSH agent.•CVE-2025-15224

References

Sources include official advisories and independent security research.