Red Hat Software Collections update for rh-varnish6-varnish

1) Inconsistent interpretation of HTTP requests

EUVDB-ID: #VU55501

Risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-36740

CWE-ID: CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling')

Exploit availability: No

Description

The vulnerability allows a remote attacker to preform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP/2 requests. A remote attacker can send a specially crafted HTTP/2 POST request with a large Content-Length header to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache or bypass VCL authorization.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

rh-varnish6-varnish-modules (Red Hat package): 0.15.0-6.el7

rh-varnish6-varnish (Red Hat package): 6.0.6-1.el7

Red Hat Software Collections: 1 for RHEL 7 - 1 for RHEL 7.7

External links

http://access.redhat.com/errata/RHSA-2021:2993

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.