01 Record

CVE-2021-21703

PHP-FPM memory access in root process leading to privilege escalation

HighPUBLISHEDCNA: php

CNA base score7.8 CVSS v3.xCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

View raw JSON

02 Description

PHP-FPM memory access in root process leading to privilege escalation

03 Exploitation and scoring

Exploitation: Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
SSVC decision: Not assessed by CISA
EPSS probability: 1.42% probability of exploitation activity in the next 30 days.
EPSS percentile: Equal to or higher than the score of 72.7% of scored records. A rank, not a probability.
NVD base score: 7.0 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD analysis status: Modified. NVD last modified this record on 2026-06-17.
Red Hat severity: Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published

2021-10-25 05:40Z5 YR AGO

Last updated

2024-09-17 03:02Z2 YR AGO

Reserved

2021-01-04

Assigning CNA

php

Record state

PUBLISHED

Severity

High (CVSS 7.8)

CNA CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

Weaknesses

CWE-284Improper Access ControlPillar
CWE-787Out-of-bounds WriteBase
CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass

Data version

5.1

Document digest

a23c869d0ba2d06d66f5265dc4dbffab33ac0b19c36c8b6e50b5a48bd5ee1efd

05 Affected products

VendorProductVersionsPlatforms

PHP GroupPHP7.3.x to 7.3.31, 7.4.x to < 7.4.25, 8.0.X to < 8.0.12—

06 References

bugs.php.nethttps://bugs.php.net/bug.php?id=81026x_refsource_MISC
www.debian.orgDSA-4992https://www.debian.org/security/2021/dsa-4992vendor-advisoryx_refsource_DEBIAN
www.debian.orgDSA-4993https://www.debian.org/security/2021/dsa-4993vendor-advisoryx_refsource_DEBIAN
www.openwall.com[oss-security] 20211026 CVE-2021-21703: PHP-FPM 5.3.7 <= 8.0.12 Local Roothttp://www.openwall.com/lists/oss-security/2021/10/26/7mailing-listx_refsource_MLIST
lists.debian.org[debian-lts-announce] 20211027 [SECURITY] [DLA 2794-1] php7.0 security updatehttps://lists.debian.org/debian-lts-announce/2021/10/msg00021.htmlmailing-listx_refsource_MLIST
lists.fedoraproject.orgFEDORA-2021-9f68f5f752https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/vendor-advisoryx_refsource_FEDORA
lists.fedoraproject.orgFEDORA-2021-4140b54de2https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/vendor-advisoryx_refsource_FEDORA
lists.fedoraproject.orgFEDORA-2021-02d218c3behttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/vendor-advisoryx_refsource_FEDORA
www.oracle.comhttps://www.oracle.com/security-alerts/cpujan2022.htmlx_refsource_MISC
security.netapp.comhttps://security.netapp.com/advisory/ntap-20211118-0003/x_refsource_CONFIRM
www.oracle.comhttps://www.oracle.com/security-alerts/cpuapr2022.htmlx_refsource_MISC
security.gentoo.orgGLSA-202209-20https://security.gentoo.org/glsa/202209-20vendor-advisoryx_refsource_GENTOO

07 Fixed in

AlmaLinux 8

apcu-panel
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
libzip
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
libzip-devel
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
libzip-tools
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
php
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-bcmath
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-cli
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-common
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-dba
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-dbg
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-devel
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-embedded
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-enchant
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-ffi
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-fpm
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-gd
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-gmp
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-intl
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-json
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-ldap
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-mbstring
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-mysqlnd
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-odbc
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-opcache
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-pdo
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-pear
Fixed in 1:1.10.12-1.module_el8.6.0+2750+78feabcb
php-pecl-apcu
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
php-pecl-apcu-devel
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
php-pecl-rrd
Fixed in 2.0.1-1.module_el8.6.0+2750+78feabcb
php-pecl-xdebug
Fixed in 2.9.5-1.module_el8.6.0+2750+78feabcb
php-pecl-zip
Fixed in 1.18.2-1.module_el8.6.0+2750+78feabcb
php-pgsql
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-process
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-snmp
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-soap
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-xml
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-xmlrpc
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb

Arch Linux

php
Fixed in 8.0.12-1

Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.

CloudLinux 8

apcu-panel
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
libzip
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
libzip-devel
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
libzip-tools
Fixed in 1.6.1-1.module_el8.6.0+2750+78feabcb
php
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-bcmath
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-cli
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-common
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-dba
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-dbg
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-devel
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-embedded
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-enchant
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-ffi
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-fpm
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-gd
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-gmp
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-intl
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-json
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-ldap
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-mbstring
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-mysqlnd
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-odbc
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-opcache
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-pdo
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-pear
Fixed in 1:1.10.12-1.module_el8.6.0+2750+78feabcb
php-pecl-apcu
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
php-pecl-apcu-devel
Fixed in 5.1.18-1.module_el8.6.0+2750+78feabcb
php-pecl-rrd
Fixed in 2.0.1-1.module_el8.6.0+2750+78feabcb
php-pecl-xdebug
Fixed in 2.9.5-1.module_el8.6.0+2750+78feabcb
php-pecl-zip
Fixed in 1.18.2-1.module_el8.6.0+2750+78feabcb
php-pgsql
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-process
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-snmp
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-soap
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-xml
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb
php-xmlrpc
Fixed in 7.4.19-2.module_el8.6.0+2750+78feabcb

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

Debian 11

php7.4
Fixed in 7.4.25-1+deb11u1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 18.04 LTS

php7.2
Fixed in 7.2.24-0ubuntu0.18.04.10

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 20.04 LTS

php7.4
Fixed in 7.4.3-4ubuntu2.7

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 14.04 LTS

php5
Fixed in 5.5.9+dfsg-1ubuntu4.29+esm15
Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 16.04 LTS

php7.0
Fixed in 7.0.33-0ubuntu0.16.04.16+esm2
Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.