CVE-2017-1000101

Published Oct 5, 2017

Last updated 10 days ago

Overview

Description
curl supports "globbing" of URLs, in which a user can pass a numerical range to have the tool iterate over those numbers to do a sequence of transfers. In the globbing function that parses the numerical range, there was an omission that made curl read a byte beyond the end of the URL if given a carefully crafted, or just wrongly written, URL. The URL is stored in a heap based buffer, so it could then be made to wrongly read something else instead of crashing. An example of a URL that triggers the flaw would be `http://ur%20[0-60000000000000000000`.
Source
cve@mitre.org
NVD status
Deferred
Products
curl

Risk scores

CVSS 3.1

Type
Secondary
Base score
6.5
Impact score
3.6
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Severity
MEDIUM

CVSS 3.0

Type
Primary
Base score
6.5
Impact score
3.6
Exploitability score
2.8
Vector string
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
4.3
Impact score
2.9
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:P/I:N/A:N

Weaknesses

nvd@nist.gov
CWE-119
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-119

Social media

Hype score
Not currently trending

Configurations

  1. 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