Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling of Structural Elements bug.

The remote Ubuntu 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6728-3 advisory.

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

  - Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are     subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding.
    All versions of Squid from 3.5 up to and including 5.9 configured with collapsed_forwarding on are     vulnerable. Configurations with collapsed_forwarding off or without a collapsed_forwarding directive     are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable     to upgrade should remove all collapsed_forwarding lines from their squid.conf. (CVE-2023-49288)

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

The remote Ubuntu 20.04 LTS / 22.04 LTS / 23.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6728-1 advisory.

  - Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are     subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding.
    All versions of Squid from 3.5 up to and including 5.9 configured with collapsed_forwarding on are     vulnerable. Configurations with collapsed_forwarding off or without a collapsed_forwarding directive     are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable     to upgrade should remove all collapsed_forwarding lines from their squid.conf. (CVE-2023-49288)

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

  - Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6     is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a     trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid     older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and     including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by     Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in     Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access     control: `http_access deny manager`. (CVE-2024-23638)

  - Squid is a web proxy cache. Starting in version 3.5.27 and prior to version 6.8, Squid may be vulnerable     to a Denial of Service attack against HTTP Chunked decoder due to an uncontrolled recursion bug. This     problem allows a remote attacker to cause Denial of Service when sending a crafted, chunked, encoded HTTP     Message. This bug is fixed in Squid version 6.8. In addition, patches addressing this problem for the     stable releases can be found in Squid's patch archives. There is no workaround for this issue.
    (CVE-2024-25111)

  - Squid is an open source caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Collapse     of Data into Unsafe Value bug ,Squid may be vulnerable to a Denial of Service attack against HTTP header     parsing. This problem allows a remote client or a remote server to perform Denial of Service when sending     oversized headers in HTTP messages. In versions of Squid prior to 6.5 this can be achieved if the     request_header_max_size or reply_header_max_size settings are unchanged from the default. In Squid version     6.5 and later, the default setting of these parameters is safe. Squid will emit a critical warning in     cache.log if the administrator is setting these parameters to unsafe values. Squid will not at this time     prevent these settings from being changed to unsafe values. Users are advised to upgrade to version 6.5.
    There are no known workarounds for this vulnerability. This issue is also tracked as SQUID-2024:2     (CVE-2024-25617)

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

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2024-578 advisory.

  - Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Buffer Overread bug     Squid is vulnerable to a Denial of Service attack against Squid HTTP Message processing. This bug is fixed     by Squid version 6.5. Users are advised to upgrade. There are no known workarounds for this vulnerability.
    (CVE-2023-49285)

  - Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are     subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding.
    All versions of Squid from 3.5 up to and including 5.9 configured with collapsed_forwarding on are     vulnerable. Configurations with collapsed_forwarding off or without a collapsed_forwarding directive     are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable     to upgrade should remove all collapsed_forwarding lines from their squid.conf. (CVE-2023-49288)

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

  - Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6     is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a     trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid     older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and     including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by     Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in     Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access     control: `http_access deny manager`. (CVE-2024-23638)

  - Squid is a web proxy cache. Starting in version 3.5.27 and prior to version 6.8, Squid may be vulnerable     to a Denial of Service attack against HTTP Chunked decoder due to an uncontrolled recursion bug. This     problem allows a remote attacker to cause Denial of Service when sending a crafted, chunked, encoded HTTP     Message. This bug is fixed in Squid version 6.8. In addition, patches addressing this problem for the     stable releases can be found in Squid's patch archives. There is no workaround for this issue.
    (CVE-2024-25111)

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

The remote Redhat Enterprise Linux 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2024:1153 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

  - squid: denial of service in HTTP request parsing (CVE-2023-50269)

Note that Nessus has not tested for these issues 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 multiple vulnerabilities as referenced in the RHSA-2024:0771 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

  - squid: denial of service in HTTP request parsing (CVE-2023-50269)

Note that Nessus has not tested for these issues 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 multiple vulnerabilities as referenced in the RHSA-2024:0773 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

  - squid: denial of service in HTTP request parsing (CVE-2023-50269)

Note that Nessus has not tested for these issues 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 multiple vulnerabilities as referenced in the RHSA-2024:0772 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

  - squid: denial of service in HTTP request parsing (CVE-2023-50269)

Note that Nessus has not tested for these issues 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 multiple vulnerabilities as referenced in the RHSA-2024:0397 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

  - squid: denial of service in HTTP request parsing (CVE-2023-50269)

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

The remote Redhat Enterprise Linux 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2024:0072 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

  - squid: Denial of Service in SSL Certificate validation (CVE-2023-46724)

  - squid: NULL pointer dereference in the gopher protocol code (CVE-2023-46728)

  - squid: Buffer over-read in the HTTP Message processing feature (CVE-2023-49285)

  - squid: Incorrect Check of Function Return Value In Helper Process management (CVE-2023-49286)

Note that Nessus has not tested for these issues 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-2023-7668 advisory.

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

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-2023:7668 advisory.

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

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-2023:7668 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

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 9 host has a package installed that is affected by a vulnerability as referenced in the ELSA-2023-7465 advisory.

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

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

The remote AlmaLinux 9 host has a package installed that is affected by a vulnerability as referenced in the ALSA-2023:7465 advisory.

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling     of Structural Elements bug. (CVE-2023-5824)

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 9 host has a package installed that is affected by a vulnerability as referenced in the RHSA-2023:7465 advisory.

  - squid: DoS against HTTP and HTTPS (CVE-2023-5824)

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
193789	Ubuntu 20.04 LTS : Squid vulnerability (USN-6728-3)	Nessus	Ubuntu Local Security Checks	high
193170	Ubuntu 20.04 LTS / 22.04 LTS / 23.10 : Squid vulnerabilities (USN-6728-1)	Nessus	Ubuntu Local Security Checks	high
192888	Amazon Linux 2023 : squid (ALAS2023-2024-578)	Nessus	Amazon Linux Local Security Checks	high
191572	RHEL 9 : squid (RHSA-2024:1153)	Nessus	Red Hat Local Security Checks	high
190404	RHEL 8 : squid:4 (RHSA-2024:0771)	Nessus	Red Hat Local Security Checks	high
190403	RHEL 8 : squid:4 (RHSA-2024:0773)	Nessus	Red Hat Local Security Checks	high
190402	RHEL 8 : squid:4 (RHSA-2024:0772)	Nessus	Red Hat Local Security Checks	high
189652	RHEL 8 : squid:4 (RHSA-2024:0397)	Nessus	Red Hat Local Security Checks	high
187675	RHEL 9 : squid (RHSA-2024:0072)	Nessus	Red Hat Local Security Checks	high
186736	Oracle Linux 8 : squid:4 (ELSA-2023-7668)	Nessus	Oracle Linux Local Security Checks	high
186632	Rocky Linux 8 : squid:4 (RLSA-2023:7668)	Nessus	Rocky Linux Local Security Checks	high
186618	RHEL 8 : squid:4 (RHSA-2023:7668)	Nessus	Red Hat Local Security Checks	high
186354	Oracle Linux 9 : squid (ELSA-2023-7465)	Nessus	Oracle Linux Local Security Checks	high
186220	AlmaLinux 9 : squid (ALSA-2023:7465)	Nessus	Alma Linux Local Security Checks	high
186195	RHEL 9 : squid (RHSA-2023:7465)	Nessus	Red Hat Local Security Checks	high

Detections

Analytics

CVE-2023-5824

high

Tenable Plugins

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