RHEL 7 : rpm (Unpatched Vulnerability)

high Nessus Plugin ID 195681

Synopsis

The remote Red Hat 7 host is affected by multiple vulnerabilities that will not be patched.

Description

The remote Redhat Enterprise Linux 7 host has one or more packages installed that are affected by multiple vulnerabilities that have been acknowledged by the vendor but will not be patched.

- rpm: Following symlinks to directories when installing packages allows privilege escalation (CVE-2017-7500)

- rpm: Following symlinks to files when installing packages allows privilege escalation (CVE-2017-7501)

- A flaw was found in RPM's hdrblobInit() in lib/header.c. This flaw allows an attacker who can modify the rpmdb to cause an out-of-bounds read. The highest threat from this vulnerability is to system availability. (CVE-2021-20266)

- A flaw was found in the RPM package in the read functionality. This flaw allows an attacker who can convince a victim to install a seemingly verifiable package or compromise an RPM repository, to cause RPM database corruption. The highest threat from this vulnerability is to data integrity. This flaw affects RPM versions before 4.17.0-alpha. (CVE-2021-3421)

- There is a flaw in RPM's signature functionality. OpenPGP subkeys are associated with a primary key via a binding signature. RPM does not check the binding signature of subkeys prior to importing them. If an attacker is able to add or socially engineer another party to add a malicious subkey to a legitimate public key, RPM could wrongly trust a malicious signature. The greatest impact of this flaw is to data integrity. To exploit this flaw, an attacker must either compromise an RPM repository or convince an administrator to install an untrusted RPM or public key. It is strongly recommended to only use RPMs and public keys from trusted sources. (CVE-2021-3521)

- A race condition vulnerability was found in rpm. A local unprivileged user could use this flaw to bypass the checks that were introduced in response to CVE-2017-7500 and CVE-2017-7501, potentially gaining root privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. (CVE-2021-35937)

- A symbolic link issue was found in rpm. It occurs when rpm sets the desired permissions and credentials after installing a file. A local unprivileged user could use this flaw to exchange the original file with a symbolic link to a security-critical file and escalate their privileges on the system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
(CVE-2021-35938)

- It was found that the fix for CVE-2017-7500 and CVE-2017-7501 was incomplete: the check was only implemented for the parent directory of the file to be created. A local unprivileged user who owns another ancestor directory could potentially use this flaw to gain root privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. (CVE-2021-35939)

Note that Nessus has not tested for these issues but has instead relied on the package manager's report that the package is installed.

Solution

The vendor has acknowledged the vulnerabilities but no solution has been provided. Refer to the vendor for remediation guidance.

Plugin Details

Severity: High

ID: 195681

File Name: redhat_unpatched-rpm-rhel7.nasl

Version: 1.0

Type: local

Agent: unix

Published: 5/11/2024

Updated: 5/11/2024

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.6

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2017-7500

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

CVSS Score Source: CVE-2017-7501

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:5, cpe:/o:redhat:enterprise_linux:6, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:redhat:enterprise_linux:rpm

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Available: true

Exploit Ease: Exploits are available

Vulnerability Publication Date: 10/26/2017

Reference Information

CVE: CVE-2017-7500, CVE-2017-7501, CVE-2021-20266, CVE-2021-3421, CVE-2021-3521, CVE-2021-35937, CVE-2021-35938, CVE-2021-35939