Debian DSA-4992-1 : php7.4 - security update

high Nessus Plugin ID 154432

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Synopsis

The remote Debian host is missing a security-related update.

Description

The remote Debian 11 host has packages installed that are affected by a vulnerability as referenced in the dsa-4992 advisory.

- In PHP versions 7.3.x up to and including 7.3.31, 7.4.x below 7.4.25 and 8.0.x below 8.0.12, when running PHP FPM SAPI with main FPM daemon process running as root and child worker processes running as lower- privileged users, it is possible for the child processes to access memory shared with the main process and write to it, modifying it in a way that would cause the root process to conduct invalid memory reads and writes, which can be used to escalate privileges from local unprivileged user to the root user.
(CVE-2021-21703)

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

Solution

Upgrade the php7.4 packages.

For the stable distribution (bullseye), this problem has been fixed in version 7.4.25-1+deb11u1.

See Also

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=997003

https://security-tracker.debian.org/tracker/source-package/php7.4

https://www.debian.org/security/2021/dsa-4992

https://security-tracker.debian.org/tracker/CVE-2021-21703

https://packages.debian.org/source/bullseye/php7.4

Plugin Details

Severity: High

ID: 154432

File Name: debian_DSA-4992.nasl

Version: 1.3

Type: local

Agent: unix

Published: 10/26/2021

Updated: 10/29/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2021-21703

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:debian:debian_linux:libapache2-mod-php7.4, p-cpe:/a:debian:debian_linux:libphp7.4-embed, p-cpe:/a:debian:debian_linux:php7.4, p-cpe:/a:debian:debian_linux:php7.4-bcmath, p-cpe:/a:debian:debian_linux:php7.4-bz2, p-cpe:/a:debian:debian_linux:php7.4-cgi, p-cpe:/a:debian:debian_linux:php7.4-cli, p-cpe:/a:debian:debian_linux:php7.4-common, p-cpe:/a:debian:debian_linux:php7.4-curl, p-cpe:/a:debian:debian_linux:php7.4-dba, p-cpe:/a:debian:debian_linux:php7.4-dev, p-cpe:/a:debian:debian_linux:php7.4-enchant, p-cpe:/a:debian:debian_linux:php7.4-fpm, p-cpe:/a:debian:debian_linux:php7.4-gd, p-cpe:/a:debian:debian_linux:php7.4-gmp, p-cpe:/a:debian:debian_linux:php7.4-imap, p-cpe:/a:debian:debian_linux:php7.4-interbase, p-cpe:/a:debian:debian_linux:php7.4-intl, p-cpe:/a:debian:debian_linux:php7.4-json, p-cpe:/a:debian:debian_linux:php7.4-ldap, p-cpe:/a:debian:debian_linux:php7.4-mbstring, p-cpe:/a:debian:debian_linux:php7.4-mysql, p-cpe:/a:debian:debian_linux:php7.4-odbc, p-cpe:/a:debian:debian_linux:php7.4-opcache, p-cpe:/a:debian:debian_linux:php7.4-pgsql, p-cpe:/a:debian:debian_linux:php7.4-phpdbg, p-cpe:/a:debian:debian_linux:php7.4-pspell, p-cpe:/a:debian:debian_linux:php7.4-readline, p-cpe:/a:debian:debian_linux:php7.4-snmp, p-cpe:/a:debian:debian_linux:php7.4-soap, p-cpe:/a:debian:debian_linux:php7.4-sqlite3, p-cpe:/a:debian:debian_linux:php7.4-sybase, p-cpe:/a:debian:debian_linux:php7.4-tidy, p-cpe:/a:debian:debian_linux:php7.4-xml, p-cpe:/a:debian:debian_linux:php7.4-xmlrpc, p-cpe:/a:debian:debian_linux:php7.4-xsl, p-cpe:/a:debian:debian_linux:php7.4-zip, cpe:/o:debian:debian_linux:11.0

Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 10/25/2021

Vulnerability Publication Date: 10/25/2021

Reference Information

CVE: CVE-2021-21703

IAVA: 2021-A-0503