Curl

This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy handshake. When curl is asked to pass along the host name to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that host name can be is 255…

Heap buffer overflow in the TFTP protocol handler in cURL 7.19.4 to 7.65.3.

libcurl versions from 7.36.0 to before 7.64.0 are vulnerable to a stack-based buffer overflow. The function creating an outgoing NTLM type-3 header (`lib/vauth/ntlm.c:Curl_auth_create_ntlm_type3_message()`), generates the request HTTP header contents based on previously received…

The FTP wildcard function in curl and libcurl before 7.57.0 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) or possibly have unspecified other impact via a string that ends with an '[' character.

Multiple integer overflows in the (1) curl_escape, (2) curl_easy_escape, (3) curl_unescape, and (4) curl_easy_unescape functions in libcurl before 7.50.3 allow attackers to have unspecified impact via a string of length 0xffffffff, which triggers a heap-based buffer overflow.

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…

When curl < 7.84.0 saves cookies, alt-svc and hsts data to local files, it makes the operation atomic by finalizing the operation with a rename from a temporary name to the final target file name.In that rename operation, it might accidentally *widen* the permissions for the…

Curl before 7.49.1 in Apple OS X before macOS Sierra prior to 10.12 allows remote or local attackers to execute arbitrary code, gain sensitive information, cause denial-of-service conditions, bypass security restrictions, and perform unauthorized actions. This may aid in other…

Double-free vulnerability in the FTP-kerberos code in cURL 7.52.0 to 7.65.3.

curl version curl 7.54.1 to and including curl 7.59.0 contains a CWE-122: Heap-based Buffer Overflow vulnerability in denial of service and more that can result in curl might overflow a heap based memory buffer when closing down an FTP connection with very long server command…

The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when built for Windows CE using the schannel TLS backend, allows remote attackers to obtain sensitive information, cause a denial of service (crash), or possibly have unspecified other…

curl, as shipped in Red Hat Enterprise Linux 6 before version 7.19.7-53, did not correctly backport the fix for CVE-2015-3148 because it did not reflect the fact that the HAVE_GSSAPI define was meanwhile substituted by USE_HTTP_NEGOTIATE. This issue was introduced in RHEL 6.7…

curl and libcurl before 7.57.0 on 32-bit platforms allow attackers to cause a denial of service (out-of-bounds access and application crash) or possibly have unspecified other impact because too little memory is allocated for interfacing to an SSL library.

The NTLM authentication feature in curl and libcurl before 7.57.0 on 32-bit platforms allows attackers to cause a denial of service (integer overflow and resultant buffer overflow, and application crash) or possibly have unspecified other impact via vectors involving long user…

When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a pointer to an already freed memory area and both use that again in a subsequent call to send data and also free it *again*.

A buffer over-read exists in curl 7.20.0 to and including curl 7.58.0 in the RTSP+RTP handling code that allows an attacker to cause a denial of service or information leakage

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…

When an application tells libcurl it wants to allow HTTP/2 server push, and the amount of received headers for the push surpasses the maximum allowed limit (1000), libcurl aborts the server push. When aborting, libcurl inadvertently does not free all the previously allocated…

A cleartext transmission of sensitive information vulnerability exists in curl <v7.88.0 that could cause HSTS functionality fail when multiple URLs are requested serially. Using its HSTS support, curl can be instructed to use HTTPS instead of usingan insecure clear-text HTTP…

A buffer overflow exists in curl 7.12.3 to and including curl 7.58.0 in the FTP URL handling that allows an attacker to cause a denial of service or worse.

Multiple stack-based buffer overflows in libcURL and cURL 7.12.1, and possibly other versions, allow remote malicious web servers to execute arbitrary code via base64 encoded replies that exceed the intended buffer lengths when decoded, which is not properly handled by (1) the…

libcurl had a flaw that when instructed to clear proxy authentication credentials which made it not do so, leaving the old credentials around to get used for subsequent transfers that should not know nor use them.

The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing the pointer in between, making it `free()` the same pointer twice.

Successfully using libcurl to do a transfer to a specific HTTP origin (`hostA`) with **Digest** authentication and then changing the origin to a different one (`hostB`) for a second transfer, reusing the same handle, makes libcurl wrongly pass on the `Authorization:` header…

A use-after-free vulnerability exists in libcurl when an application configures an HTTP/2 stream-dependency tree via `CURLOPT_STREAM_DEPENDS` or `CURLOPT_STREAM_DEPENDS_E`, subsequently invokes `curl_easy_reset()`, and finally terminates the handle with `curl_easy_cleanup()`.…

A path traversal vulnerability exists in curl <8.0.0 SFTP implementation causes the tilde (~) character to be wrongly replaced when used as a prefix in the first path element, in addition to its intended use as the first element to indicate a path relative to the user's home…

A vulnerability in input validation exists in curl <8.0 during communication using the TELNET protocol may allow an attacker to pass on maliciously crafted user name and "telnet options" during server negotiation. The lack of proper input scrubbing allows an attacker to send…

libcurl 7.1 through 7.57.0 might accidentally leak authentication data to third parties. When asked to send custom headers in its HTTP requests, libcurl will send that set of headers first to the host in the initial URL but also, if asked to follow redirects and a 30X HTTP…

A heap buffer overflow in the TFTP receiving code allows for DoS or arbitrary code execution in libcurl versions 7.19.4 through 7.64.1.

When curl retrieves an HTTP response, it stores the incoming headers so that they can be accessed later via the libcurl headers API. However, curl did not have a limit in how many or how large headers it would accept in a response, allowing a malicious server to stream an…

curl before 7.86.0 has a double free. If curl is told to use an HTTP proxy for a transfer with a non-HTTP(S) URL, it sets up the connection to the remote server by issuing a CONNECT request to the proxy, and then tunnels the rest of the protocol through. An HTTP proxy might…

A use of incorrectly resolved name vulnerability fixed in 7.83.1 might remove the wrong file when `--no-clobber` is used together with `--remove-on-error`.

curl version curl 7.20.0 to and including curl 7.59.0 contains a CWE-126: Buffer Over-read vulnerability in denial of service that can result in curl can be tricked into reading data beyond the end of a heap based buffer used to store downloaded RTSP content.. This vulnerability…

The verify_certificate function in lib/vtls/schannel.c in libcurl 7.30.0 through 7.51.0, when built for Windows CE using the schannel TLS backend, makes it easier for remote attackers to conduct man-in-the-middle attacks via a crafted wildcard SAN in a server certificate, as…

When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against `proxyA` using Digest auth, a subsequent…

When asking curl to use a `.netrc` file to find credentials and at the same time specifying a URL with a username(without a password), like `https://[email protected]/`, curl could wrongly get and use the password for *another* user set in the `.netrc` file for that host if such…

A flaw in curl’s cookie parsing logic allows a malicious HTTP server to set 'super cookies' that bypass the Public Suffix List check. This enables an attacker-controlled origin to inject cookies that curl subsequently scopes and transmits to unrelated third-party domains.

libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. An easy handle that first uses default native CA trust can continue trusting the native platform store after the application switches that same…

curl 7.20.0 through 7.70.0 is vulnerable to improper restriction of names for files and other resources that can lead too overwriting a local file when the -J flag is used.

A non-privileged user or program can put code and a config file in a known non-privileged path (under C:/usr/local/) that will make curl <= 7.65.1 automatically run the code (as an openssl "engine") on invocation. If that curl is invoked by a privileged user it can do anything…

Multiple untrusted search path vulnerabilities in cURL and libcurl before 7.49.1, when built with SSPI or telnet is enabled, allow local users to execute arbitrary code and conduct DLL hijacking attacks via a Trojan horse (1) security.dll, (2) secur32.dll, or (3) ws2_32.dll in…

A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provided in the URL. However, the HSTS…

libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use the macOS native TLS library Secure Transport, an application can ask…

curl and libcurl before 7.50.1 do not check the client certificate when choosing the TLS connection to reuse, which might allow remote attackers to hijack the authentication of the connection by leveraging a previously created connection with a different client certificate.

curl and libcurl before 7.50.1 do not prevent TLS session resumption when the client certificate has changed, which allows remote attackers to bypass intended restrictions by resuming a session.

When doing a second SMB request to the same host again, curl would wrongly use a data pointer pointing into already freed memory.

Due to a mistake in libcurl's WebSocket code, a malicious server can send a particularly crafted packet which makes libcurl get trapped in an endless busy-loop. There is no other way for the application to escape or exit this loop other than killing the thread/process. This…

libcurl's ASN1 parser has this utf8asn1str() function used for parsing an ASN.1 UTF-8 string. Itcan detect an invalid field and return error. Unfortunately, when doing so it also invokes `free()` on a 4 byte localstack buffer. Most modern malloc implementations detect this…

A use after free vulnerability exists in curl <v8.1.0 in the way libcurl offers a feature to verify an SSH server's public key using a SHA 256 hash. When this check fails, libcurl would free the memory for the fingerprint before it returns an error message containing the (now…

In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step) even when HTTP is provided in the URL. This mechanism could be…