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7.35. curl

Updated curl packages that fix multiple security issues, several bugs, and add two enhancements are now available for Red Hat Enterprise Linux 6.
Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.
The curl packages provide the libcurl library and the curl utility for downloading files from servers using various protocols, including HTTP, FTP, and LDAP.

Security Fixes

It was found that the libcurl library did not correctly handle partial literal IP addresses when parsing received HTTP cookies. An attacker able to trick a user into connecting to a malicious server could use this flaw to set the user's cookie to a crafted domain, making other cookie-related issues easier to exploit.
A flaw was found in the way the libcurl library performed the duplication of connection handles. If an application set the CURLOPT_COPYPOSTFIELDS option for a handle, using the handle's duplicate could cause the application to crash or disclose a portion of its memory.
It was discovered that the libcurl library failed to properly handle URLs with embedded end-of-line characters. An attacker able to make an application using libcurl to access a specially crafted URL via an HTTP proxy could use this flaw to inject additional headers to the request or construct additional requests.
CVE-2015-3143, CVE-2015-3148
It was discovered that libcurl implemented aspects of the NTLM and Negotatiate authentication incorrectly. If an application uses libcurl and the affected mechanisms in a specifc way, certain requests to a previously NTLM-authenticated server could appears as sent by the wrong authenticated user. Additionally, the initial set of credentials for HTTP Negotiate-authenticated requests could be reused in subsequent requests, although a different set of credentials was specified.
Red Hat would like to thank the cURL project for reporting these issues.

Bug Fixes

An out-of-protocol fallback to SSL version 3.0 (SSLv3.0) was available with libcurl. Attackers could abuse the fallback to force downgrade of the SSL version. The fallback has been removed from libcurl. Users requiring this functionality can explicitly enable SSLv3.0 through the libcurl API.
A single upload transfer through the FILE protocol opened the destination file twice. If the inotify kernel subsystem monitored the file, two events were produced unnecessarily. The file is now opened only once per upload.
Utilities using libcurl for SCP/SFTP transfers could terminate unexpectedly when the system was running in FIPS mode.
Using the "--retry" option with the curl utility could cause curl to terminate unexpectedly with a segmentation fault. Now, adding "--retry" no longer causes curl to crash.
The "curl --trace-time" command did not use the correct local time when printing timestamps. Now, "curl --trace-time" works as expected.
The valgrind utility could report dynamically allocated memory leaks on curl exit. Now, curl performs a global shutdown of the NetScape Portable Runtime (NSPR) library on exit, and valgrind no longer reports the memory leaks.
Previously, libcurl returned an incorrect value of the CURLINFO_HEADER_SIZE field when a proxy server appended its own headers to the HTTP response. Now, the returned value is valid.
Red Hat would like to thank the cURL project for reporting these issues.


The "--tlsv1.0", "--tlsv1.1", and "--tlsv1.2" options are available for specifying the minor version of the TLS protocol to be negotiated by NSS. The "--tlsv1" option now negotiates the highest version of the TLS protocol supported by both the client and the server.
BZ#1058767, BZ#1156422
It is now possible to explicitly enable or disable the ECC and the new AES cipher suites to be used for TLS.
All curl users are advised to upgrade to these updated packages, which contain backported patches to correct these issues and add these enhancements.