curl: TFTP upload ignores --continue-at / CURLOPT_RESUME_FROM and leaks skipped local file prefix

Summary TFTP uploads ignore the configured resume offset. When a caller runs curl -C N -T file tftp://... or uses libcurl with CURLOPTUPLOAD and CURLOPTRESUMEFROM, curl should skip the first N bytes of the local source before uploading. Instead, the TFTP code sends the complete local file from by...

curl: CURLOPT_COOKIE leaked to cross-origin redirect target — CURLOPT_UNRESTRICTED_AUTH bypass for the STRING_COOKIE path

Summary: httpcookies at lib/http.c:2532-2534 appends the value of CURLOPTCOOKIE the cookie supplied via -b to outgoing Cookie: headers without invoking Curlauthallowedtohost. As a result, when CURLOPTFOLLOWLOCATION is enabled and the initial origin issues a cross-origin redirect open redirector,...

EUVD-2026-29923

libcurl might in some circumstances reuse the wrong connection when asked to do an authenticated HTTPS request after a Negotiate-authenticated one, when both use the same host. libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid...

CURL-CVE-2026-7168 cross-proxy Digest auth state leak

Successfully using libcurl to do a transfer over a specific HTTP proxy proxyA with Digest authentication and then changing the proxy host to a second one proxyB for a second transfer, reusing the same handle, makes libcurl wrongly pass on the Proxy-Authorization: header field meant for proxyA, to...

MiracleLinux 7 : curl-7.29.0-42.el7.1 (AXSA:2017-2424:02)

The remote MiracleLinux 7 host has packages installed that are affected by a vulnerability as referenced in the AXSA:2017-2424:02 advisory. A buffer overrun flaw was found in the IMAP handler of libcurl. By tricking an unsuspecting user into connecting to a malicious IMAP server, an attacker coul...

RHEL 9 : curl (RHSA-2025:23043)

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2025:23043 advisory. The curl packages provide the libcurl library and the curl utility for downloading files from servers using various protocols, including HTTP, FTP,...

Siemens SIMATIC and SCALANCE Multiple Releases of Same Resource or Handle (CVE-2025-0665)

libcurl would wrongly close the same eventfd file descriptor twice when taking down a connection channel after having completed a threaded name resolve. This plugin only works with Tenable.ot. Please visit https://www.tenable.com/products/tenable-ot for more information. %NASLMINLEVEL 80900 C...

SUSE CVE-2025-4947

libcurl accidentally skips the certificate verification for QUIC connections when connecting to a host specified as an IP address in the URL. Therefore, it does not detect impostors or man-in-the-middle attacks...

Astra Linux – Vulnerability in curl

When an application instructs libcurl to enable HTTP/2 server push, and the number of received headers for the push exceeds the maximum allowed limit 1000, libcurl abends the server push. During this process, libcurl inadvertently does not free all of the previously allocated headers; instead, it...

When doing HTTP(S) transfers libcurl might erroneously use the read callback (`CURLOPT_READFUNCTION`) to ask for data to send even when the `CURLOPT_POSTFIELDS` option has been set if the same handle previously was used to issue a `PUT` request which used that callback. This flaw may surprise the application and cause it to misbehave and either send off the wrong data or use memory after free or similar in the subsequent `POST` request. The problem exists in the logic for a reused handle when it is changed from a PUT to a POST.

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curl: CVE-2023-28322: more POST-after-PUT confusion

A vulnerability existed in libcurl that allowed an attacker to inject unintended data or cause a segfault by confusing the POST and PUT methods. The previous fix for this vulnerability was insufficient as it only corrected the CURLOPTPOST option, which is not always used when sending data with th...

SUSE CVE-2017-1000257

An IMAP FETCH response line indicates the size of the returned data, in number of bytes. When that response says the data is zero bytes, libcurl would pass on that non-existing data with a pointer and the size zero to the deliver-data function. libcurl's deliver-data function treats zero as a mag...

AZL-38548 CVE-2022-32221 affecting package tensorflow for versions less than 2.16.1-1

When doing HTTPS transfers, libcurl might erroneously use the read callback CURLOPTREADFUNCTION to ask for data to send, even when the CURLOPTPOSTFIELDS option has been set, if the same handle previously was used to issue a PUT request which used that callback. This flaw may surprise the...

wrong connect-only connection

An application that performs multiple requests with libcurl's multi API and sets the CURLOPTCONNECTONLY option, might in rare circumstances experience that when subsequently using the setup connect-only transfer, libcurl picks and uses the wrong connection - and instead picks another one the...

curl: HTTP authentication leak in redirects

It was found that curl and libcurl might send their Authentication header to a third party HTTP server upon receiving an HTTP REDIRECT reply. This could leak authentication token to external entities...

ALPINE-CVE-2017-1000257

An IMAP FETCH response line indicates the size of the returned data, in number of bytes. When that response says the data is zero bytes, libcurl would pass on that non-existing data with a pointer and the size zero to the deliver-data function. libcurl's deliver-data function treats zero as a mag...

CURL-CVE-2014-3707 duphandle read out of bounds

libcurl's function curleasyduphandle has a bug that can lead to libcurl eventually sending off sensitive data that was not intended for sending. When doing an HTTP POST transfer with libcurl, you can use the CURLOPTCOPYPOSTFIELDS option to specify a memory area holding the data to send to the...

CURL-CVE-2013-1944 cookie domain tailmatch

libcurl is vulnerable to a cookie leak vulnerability when doing requests across domains with matching tails. When communicating over HTTPS and having libcurl's cookie engine enabled, libcurl stores and holds cookies for use when subsequent requests are done to hosts and paths that match those kep...