cURL libcurl is vulnerable to a stack-based buffer overflow, caused by improper bounds checking by the toolcbwrt component. By sending a specially crafted request, a remote attacker could overflow a buffer and execute arbitrary code or cause a denial of service condition on the system.
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 attacks.
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.
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 HAVEGSSAPI define was meanwhile substituted by USEHTTPNEGOTIATE. This issue was introduced in RHEL 6.7 and affects RHEL 6 curl only.
The verifycertificate 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 impact via a wildcard certificate name, which triggers an out-of-bounds read.
The fixhostname function in cURL and libcurl 7.37.0 through 7.41.0 does not properly calculate an index, which allows remote attackers to cause a denial of service (out-of-bounds read or write and crash) or possibly have other unspecified impact via a zero-length host name, as demonstrated by "http://:80" and ":80."
The verifycertificate 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 demonstrated by ".com."
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) ws232.dll in the application or current working directory.
By default, curl automatically responds to WebSocket PING frames. Because curl lacks an upper bound on memory allocation for unacknowledged frames, a malicious server can exhaust all available memory by flooding curl with rapid, sequential PING messages.
An issue in curl’s QUIC UDP receive function allows a malicious HTTP/3 server to trigger a remote denial of service against a curl or libcurl client. Because the helper function discards zero-length UDP datagrams before counting them toward the per-call packet budget, a connected QUIC peer can continuously stream empty datagrams to indefinitely stall the client.
A Set-Cookie: header using tab (horizontal tab, ASCII code 9) instead of space (ascii code 32) immediately before the Secure attribute causes curl to store the cookie without its Secure flag. The cookie might then wrongfully be sent over plaintext HTTP on subsequent requests to the same host.
Stack-based buffer overflow in the Curlsaslcreatedigestmd5message function in lib/curlsasl.c in curl and libcurl 7.26.0 through 7.28.1, when negotiating SASL DIGEST-MD5 authentication, allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long string in the realm parameter in a (1) POP3, (2) SMTP or (3) IMAP message.
The sanitizecookiepath function in cURL and libcurl 7.31.0 through 7.41.0 does not properly calculate an index, which allows remote attackers to cause a denial of service (out-of-bounds write and crash) or possibly have other unspecified impact via a cookie path containing only a double-quote character.
lib/curl.rb in the Curl Gem for Ruby allows remote attackers to execute arbitrary commands via shell metacharacters in a URL.
The ConnectionExists function in lib/url.c in libcurl before 7.47.0 does not properly re-use NTLM-authenticated proxy connections, which might allow remote attackers to authenticate as other users via a request, a similar issue to CVE-2014-0015.
When a user invokes curl using a schemeless URL combined with --proto-default sftp (or scp), a disconnect occurs between the tool layer and libcurl. The tool layer incorrectly infers the URL scheme, which erroneously bypasses the initialization of critical SSH security options like CURLOPTSSHHOSTPUBLICKEYSHA256 and CURLOPTSSHKNOWNHOSTS. Conversely, the libcurl runtime successfully honors CURLOPTDEFAULTPROTOCOL and establishes the connection via SFTP/SCP as specified. Because the tool layer skipped the security configuration, these SSH host verification options are silently omitted, causing curl to connect to an unverified SSH remote host without throwing an error.
On October 11, 2023, cURL released Version 8.4.0 of the cURL utility and the libcurl library. This release addressed two security vulnerabilities: CVE-2023-38545 - High Security Impact Rating (SIR)CVE-2023-38546 - Low SIRThis
Heap-based buffer overflow in the curleasyunescape function in lib/escape.c in cURL and libcurl 7.7 through 7.30.0 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted string ending in a "%" (percent) character.
curl before 7.53.0 has an incorrect TLS Certificate Status Request extension feature that asks for a fresh proof of the server's certificate's validity in the code that checks for a test success or failure. It ends up always thinking there's valid proof, even when there is none or if the server doesn't support the TLS extension in question. This could lead to users not detecting when a server's certificate goes invalid or otherwise be mislead that the server is in a better shape than it is in reality. This flaw also exists in the command line tool (--cert-status).
The smbrequeststate function in cURL and libcurl 7.40.0 through 7.42.1 allows remote SMB servers to obtain sensitive information from memory or cause a denial of service (out-of-bounds read and crash) via crafted length and offset values.
php-mod/curl (a wrapper of the PHP cURL extension) before 2.3.2 allows XSS via the postfilepathupload.php key parameter and the POST data to postmultidimensional.php.
Absolute path traversal vulnerability in curl 7.20.0 through 7.21.1, when the --remote-header-name or -J option is used, allows remote servers to create or overwrite arbitrary files by using \ (backslash) as a separator of path components within the Content-disposition HTTP header.
802.1X. An authentication issue was addressed with improved state management.
cURL before 7.47.0 on Windows allows attackers to write to arbitrary files in the current working directory on a different drive via a colon in a remote file name.
The (1) mbedconnectstep1 function in lib/vtls/mbedtls.c and (2) polarsslconnectstep1 function in lib/vtls/polarssl.c in cURL and libcurl before 7.49.0, when using SSLv3 or making a TLS connection to a URL that uses a numerical IP address, allow remote attackers to spoof servers via an arbitrary valid certificate.
A security flaw was found in the way the library of cURL, an utility for retrieval of files from remote servers, performed match of cookie domain names when making a decision if (previously stored cookies) should be sent to particular domain. Due to a bug in match function implementation, (formerly) the decision / match succeeded also in cases, where just suffix / certain part of the domain name matched the domain name, the current request originated from. A remote attacker could use this flaw to possibly hijack the user session of the victim by submitting a request containing a specially-crafted domain name.
References: [1] http://thread.gmane.org/gmane.comp.web.curl.library/38986
Acknowledgements:
Red Hat would like to thank the cURL project for reporting this issue. Upstream acknowledges YAMADA Yasuharu as the original reporter.
cURL and libcurl before 7.38.0 does not properly handle IP addresses in cookie domain names, which allows remote attackers to set cookies for or send arbitrary cookies to certain sites, as demonstrated by a site at 192.168.0.1 setting cookies for a site at 127.168.0.1.
cURL and libcurl before 7.38.0 allow remote attackers to bypass the Same Origin Policy and set cookies for arbitrary sites by setting a cookie for a top-level domain.
The default configuration for cURL and libcurl before 7.42.1 sends custom HTTP headers to both the proxy and destination server, which might allow remote proxy servers to obtain sensitive information by reading the header contents.
cURL and libcurl 7.10.6 through 7.41.0 does not properly re-use NTLM connections, which allows remote attackers to connect as other users via an unauthenticated request, a similar issue to CVE-2014-0015.