Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8.

The remote CentOS Linux 9 host has packages installed that are affected by a vulnerability as referenced in the varnish-6.5.2-2.el9 build changelog.

  - HTTP/2 request smuggling attack via a large Content-Length header for a POST request (CVE-2021-36740)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Rocky Linux 8 host has packages installed that are affected by a vulnerability as referenced in the RLSA-2021:2988 advisory.

  - Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large     Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and     Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8. (CVE-2021-36740)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-5474-1 advisory.

    It was dicovered that Varnish Cache did not clear a pointer between the handling of one client request and     the next request within the same connection. A remote attacker could possibly use this issue to obtain     sensitive information. (CVE-2019-20637)

    It was discovered that Varnish Cache could have an assertion failure when a TLS termination proxy uses     PROXY version 2. A remote attacker could possibly use this issue to restart the daemon and cause a     performance loss. (CVE-2020-11653)

    It was discovered that Varnish Cache allowed request smuggling and VCL authorization bypass via a large     Content-Length header for a POST request. A remote attacker could possibly use this issue to obtain     sensitive information. (CVE-2021-36740)

    It was discovered that Varnish Cache allowed request smuggling for HTTP/1 connections. A remote attacker     could possibly use this issue to obtain sensitive information. (CVE-2022-23959)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SUSE15 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2022:0148-1 advisory.

  - Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large     Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and     Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8. (CVE-2021-36740)

  - In Varnish Cache before 6.6.2 and 7.x before 7.0.2, Varnish Cache 6.0 LTS before 6.0.10, and and Varnish     Enterprise (Cache Plus) 4.1.x before 4.1.11r6 and 6.0.x before 6.0.9r4, request smuggling can occur for     HTTP/1 connections. (CVE-2022-23959)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 10 / 11 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-5088 advisory.

  - Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large     Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and     Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8. (CVE-2021-36740)

  - In Varnish Cache before 6.6.2 and 7.x before 7.0.2, Varnish Cache 6.0 LTS before 6.0.10, and and Varnish     Enterprise (Cache Plus) 4.1.x before 4.1.11r6 and 6.0.x before 6.0.9r4, request smuggling can occur for     HTTP/1 connections. (CVE-2022-23959)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote CentOS Linux 8 host has packages installed that are affected by a vulnerability as referenced in the CESA-2021:2988 advisory.

  - varnish: HTTP/2 request smuggling attack via a large Content-Length header for a POST request     (CVE-2021-36740)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2021:2988 advisory.

    Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't     have to create the same web page over and over again, giving the website a significant speed up.

    Security Fix(es):

    * varnish: HTTP/2 request smuggling attack via a large Content-Length header for a POST request     (CVE-2021-36740)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2021:2993 advisory.

    Varnish Cache is a high-performance HTTP accelerator. It stores web pages in memory so web servers don't     have to create the same web page over and over again, giving the website a significant speed up.

    The following packages have been upgraded to a later upstream version: rh-varnish6-varnish (6.0.8).

    Security Fix(es):

    * varnish: HTTP/2 request smuggling attack via a large Content-Length header for a POST request     (CVE-2021-36740)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Oracle Linux 8 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2021-2988 advisory.

    - Resolves: #1982861 - CVE-2021-36740 varnish:6/varnish: HTTP/2 request       smuggling attack via a large Content-Length header for a POST request

    varnish-modules

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
191203	CentOS 9 : varnish-6.5.2-2.el9	Nessus	CentOS Local Security Checks	medium
184784	Rocky Linux 8 : varnish:6 (RLSA-2021:2988)	Nessus	Rocky Linux Local Security Checks	medium
161982	Ubuntu 18.04 LTS / 20.04 LTS / 22.04 LTS : Varnish Cache vulnerabilities (USN-5474-1)	Nessus	Ubuntu Local Security Checks	critical
161654	openSUSE 15 Security Update : varnish (openSUSE-SU-2022:0148-1)	Nessus	SuSE Local Security Checks	critical
158585	Debian DSA-5088-1 : varnish - security update	Nessus	Debian Local Security Checks	critical
152358	CentOS 8 : varnish:6 (CESA-2021:2988)	Nessus	CentOS Local Security Checks	medium
152352	RHEL 8 : varnish:6 (RHSA-2021:2988)	Nessus	Red Hat Local Security Checks	medium
152347	RHEL 7 : rh-varnish6-varnish (RHSA-2021:2993)	Nessus	Red Hat Local Security Checks	medium
152184	Oracle Linux 8 : varnish:6 (ELSA-2021-2988)	Nessus	Oracle Linux Local Security Checks	medium

Detections

Analytics

CVE-2021-36740

medium

Tenable Plugins

medium

medium

critical

critical

critical

medium

medium

medium

medium