RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
nc only supports HTTP/1.0 proxy servers and fails on HTTP/1.1 responses.

$ nc -X connect -x proxy.example.com:3128 www.example.com 443
nc: Proxy error: "HTTP/1.1 200 Connection established"
$

nc works fine without proxy or with HTTP/1.0 proxy servers, but with recent versions of Squid (always sending HTTP/1.1 responses) it fails. Proxy servers must send the highest HTTP version they support (not necessarily the same as the version of the original request).

If you look into the source code, nc expects a hardcoded "HTTP/1.0 200 " response. It shouldn't care about the HTTP version as long as it gets a positive "200" response.

Version-Release number of selected component (if applicable):
nc-1.84-22.el6.i686

How reproducible:
Use nc to connect through a HTTP/1.1 proxy.

Steps to Reproduce:
1. see above
2.
3.

Actual results:
nc aborts because of hardcoded HTTP version.

Expected results:
Happily connect and ignore the HTTP version (the "200" response is all that matters).

Additional info:
I could use "ncat" (nmap) instead but that has also an issue with HTTP proxy.

This is an easy fix and already present upstream, too.

This should be a trivial fix, please update from upstream.

A fix pushed in nc-1.84-23.el6.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHEA-2014-1968.html