Vulnerability-Lookup

OESA-2021-1430 (CVE-2021-21703)

Vulnerability from osv_openeuler – Published: 2021-11-12 11:04 – Updated: 2026-08-06 11:04 – Source website

Summary

php security update

Details

PHP is an HTML-embedded scripting language. PHP attempts to make it easy for developers to write dynamically generated web pages. PHP also offers built-in database integration for several commercial and non-commercial database management systems, so writing a database-enabled webpage with PHP is fairly simple. The most common use of PHP coding is probably as a replacement for CGI scripts. The php package contains the module (often referred to as mod_php) which adds support for the PHP language to Apache HTTP Server.

Security Fix(es):

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)

Severity

7.8 (High)


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

References

URL

Type

	https://www.openeuler.org/en/security/safety-bull…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2021-21703	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "php-xmlrpc-7.2.10-16.oe1.aarch64.rpm",
          "php-dba-7.2.10-16.oe1.aarch64.rpm",
          "php-pdo-7.2.10-16.oe1.aarch64.rpm",
          "php-gmp-7.2.10-16.oe1.aarch64.rpm",
          "php-bcmath-7.2.10-16.oe1.aarch64.rpm",
          "php-common-7.2.10-16.oe1.aarch64.rpm",
          "php-snmp-7.2.10-16.oe1.aarch64.rpm",
          "php-help-7.2.10-16.oe1.aarch64.rpm",
          "php-ldap-7.2.10-16.oe1.aarch64.rpm",
          "php-embedded-7.2.10-16.oe1.aarch64.rpm",
          "php-odbc-7.2.10-16.oe1.aarch64.rpm",
          "php-soap-7.2.10-16.oe1.aarch64.rpm",
          "php-recode-7.2.10-16.oe1.aarch64.rpm",
          "php-7.2.10-16.oe1.aarch64.rpm",
          "php-intl-7.2.10-16.oe1.aarch64.rpm",
          "php-process-7.2.10-16.oe1.aarch64.rpm",
          "php-cli-7.2.10-16.oe1.aarch64.rpm",
          "php-gd-7.2.10-16.oe1.aarch64.rpm",
          "php-dbg-7.2.10-16.oe1.aarch64.rpm",
          "php-pgsql-7.2.10-16.oe1.aarch64.rpm",
          "php-tidy-7.2.10-16.oe1.aarch64.rpm",
          "php-debugsource-7.2.10-16.oe1.aarch64.rpm",
          "php-mysqlnd-7.2.10-16.oe1.aarch64.rpm",
          "php-fpm-7.2.10-16.oe1.aarch64.rpm",
          "php-opcache-7.2.10-16.oe1.aarch64.rpm",
          "php-enchant-7.2.10-16.oe1.aarch64.rpm",
          "php-debuginfo-7.2.10-16.oe1.aarch64.rpm",
          "php-json-7.2.10-16.oe1.aarch64.rpm",
          "php-devel-7.2.10-16.oe1.aarch64.rpm",
          "php-mbstring-7.2.10-16.oe1.aarch64.rpm",
          "php-xml-7.2.10-16.oe1.aarch64.rpm"
        ],
        "src": [
          "php-7.2.10-16.oe1.src.rpm"
        ],
        "x86_64": [
          "php-common-7.2.10-16.oe1.x86_64.rpm",
          "php-debugsource-7.2.10-16.oe1.x86_64.rpm",
          "php-pdo-7.2.10-16.oe1.x86_64.rpm",
          "php-gmp-7.2.10-16.oe1.x86_64.rpm",
          "php-odbc-7.2.10-16.oe1.x86_64.rpm",
          "php-tidy-7.2.10-16.oe1.x86_64.rpm",
          "php-cli-7.2.10-16.oe1.x86_64.rpm",
          "php-dba-7.2.10-16.oe1.x86_64.rpm",
          "php-7.2.10-16.oe1.x86_64.rpm",
          "php-ldap-7.2.10-16.oe1.x86_64.rpm",
          "php-devel-7.2.10-16.oe1.x86_64.rpm",
          "php-xmlrpc-7.2.10-16.oe1.x86_64.rpm",
          "php-gd-7.2.10-16.oe1.x86_64.rpm",
          "php-mbstring-7.2.10-16.oe1.x86_64.rpm",
          "php-recode-7.2.10-16.oe1.x86_64.rpm",
          "php-opcache-7.2.10-16.oe1.x86_64.rpm",
          "php-dbg-7.2.10-16.oe1.x86_64.rpm",
          "php-json-7.2.10-16.oe1.x86_64.rpm",
          "php-process-7.2.10-16.oe1.x86_64.rpm",
          "php-xml-7.2.10-16.oe1.x86_64.rpm",
          "php-debuginfo-7.2.10-16.oe1.x86_64.rpm",
          "php-soap-7.2.10-16.oe1.x86_64.rpm",
          "php-bcmath-7.2.10-16.oe1.x86_64.rpm",
          "php-pgsql-7.2.10-16.oe1.x86_64.rpm",
          "php-embedded-7.2.10-16.oe1.x86_64.rpm",
          "php-help-7.2.10-16.oe1.x86_64.rpm",
          "php-fpm-7.2.10-16.oe1.x86_64.rpm",
          "php-enchant-7.2.10-16.oe1.x86_64.rpm",
          "php-snmp-7.2.10-16.oe1.x86_64.rpm",
          "php-intl-7.2.10-16.oe1.x86_64.rpm",
          "php-mysqlnd-7.2.10-16.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP1",
        "name": "php",
        "purl": "pkg:rpm/openEuler/php\u0026distro=openEuler-20.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.10-16.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "aarch64": [
          "php-soap-8.0.0-5.oe1.aarch64.rpm",
          "php-fpm-8.0.0-5.oe1.aarch64.rpm",
          "php-dbg-8.0.0-5.oe1.aarch64.rpm",
          "php-pdo-8.0.0-5.oe1.aarch64.rpm",
          "php-embedded-8.0.0-5.oe1.aarch64.rpm",
          "php-snmp-8.0.0-5.oe1.aarch64.rpm",
          "php-cli-8.0.0-5.oe1.aarch64.rpm",
          "php-devel-8.0.0-5.oe1.aarch64.rpm",
          "php-pgsql-8.0.0-5.oe1.aarch64.rpm",
          "php-process-8.0.0-5.oe1.aarch64.rpm",
          "php-mbstring-8.0.0-5.oe1.aarch64.rpm",
          "php-opcache-8.0.0-5.oe1.aarch64.rpm",
          "php-dba-8.0.0-5.oe1.aarch64.rpm",
          "php-ffi-8.0.0-5.oe1.aarch64.rpm",
          "php-common-8.0.0-5.oe1.aarch64.rpm",
          "php-debugsource-8.0.0-5.oe1.aarch64.rpm",
          "php-gd-8.0.0-5.oe1.aarch64.rpm",
          "php-xml-8.0.0-5.oe1.aarch64.rpm",
          "php-8.0.0-5.oe1.aarch64.rpm",
          "php-gmp-8.0.0-5.oe1.aarch64.rpm",
          "php-bcmath-8.0.0-5.oe1.aarch64.rpm",
          "php-debuginfo-8.0.0-5.oe1.aarch64.rpm",
          "php-ldap-8.0.0-5.oe1.aarch64.rpm",
          "php-enchant-8.0.0-5.oe1.aarch64.rpm",
          "php-intl-8.0.0-5.oe1.aarch64.rpm",
          "php-help-8.0.0-5.oe1.aarch64.rpm",
          "php-odbc-8.0.0-5.oe1.aarch64.rpm",
          "php-tidy-8.0.0-5.oe1.aarch64.rpm",
          "php-mysqlnd-8.0.0-5.oe1.aarch64.rpm"
        ],
        "src": [
          "php-8.0.0-5.oe1.src.rpm"
        ],
        "x86_64": [
          "php-pgsql-8.0.0-5.oe1.x86_64.rpm",
          "php-8.0.0-5.oe1.x86_64.rpm",
          "php-dbg-8.0.0-5.oe1.x86_64.rpm",
          "php-opcache-8.0.0-5.oe1.x86_64.rpm",
          "php-tidy-8.0.0-5.oe1.x86_64.rpm",
          "php-common-8.0.0-5.oe1.x86_64.rpm",
          "php-ffi-8.0.0-5.oe1.x86_64.rpm",
          "php-gd-8.0.0-5.oe1.x86_64.rpm",
          "php-dba-8.0.0-5.oe1.x86_64.rpm",
          "php-mysqlnd-8.0.0-5.oe1.x86_64.rpm",
          "php-ldap-8.0.0-5.oe1.x86_64.rpm",
          "php-enchant-8.0.0-5.oe1.x86_64.rpm",
          "php-fpm-8.0.0-5.oe1.x86_64.rpm",
          "php-devel-8.0.0-5.oe1.x86_64.rpm",
          "php-pdo-8.0.0-5.oe1.x86_64.rpm",
          "php-gmp-8.0.0-5.oe1.x86_64.rpm",
          "php-mbstring-8.0.0-5.oe1.x86_64.rpm",
          "php-odbc-8.0.0-5.oe1.x86_64.rpm",
          "php-process-8.0.0-5.oe1.x86_64.rpm",
          "php-debuginfo-8.0.0-5.oe1.x86_64.rpm",
          "php-bcmath-8.0.0-5.oe1.x86_64.rpm",
          "php-embedded-8.0.0-5.oe1.x86_64.rpm",
          "php-cli-8.0.0-5.oe1.x86_64.rpm",
          "php-intl-8.0.0-5.oe1.x86_64.rpm",
          "php-snmp-8.0.0-5.oe1.x86_64.rpm",
          "php-help-8.0.0-5.oe1.x86_64.rpm",
          "php-debugsource-8.0.0-5.oe1.x86_64.rpm",
          "php-soap-8.0.0-5.oe1.x86_64.rpm",
          "php-xml-8.0.0-5.oe1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:20.03-LTS-SP2",
        "name": "php",
        "purl": "pkg:rpm/openEuler/php\u0026distro=openEuler-20.03-LTS-SP2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8.0.0-5.oe1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "PHP is an HTML-embedded scripting language. PHP attempts to make it easy for developers to write dynamically generated web pages. PHP also offers built-in database integration for several commercial and non-commercial database management systems, so writing a database-enabled webpage with PHP is fairly simple. The most common use of PHP coding is probably as a replacement for CGI scripts. The php package contains the module (often referred to as mod_php) which adds support for the PHP language to Apache HTTP Server.\r\n\r\nSecurity Fix(es):\r\n\r\nIn 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)",
  "id": "OESA-2021-1430",
  "modified": "2026-08-06T11:04:42Z",
  "published": "2021-11-12T11:04:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1430"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-21703"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "php security update",
  "upstream": [
    "CVE-2021-21703"
  ]
}

CVE-2021-21703 (GCVE-0-2021-21703)

Vulnerability from cvelistv5 – Published: 2021-10-25 05:40 – Updated: 2024-09-17 03:02

Title

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

Summary

Severity

7.8 (High)


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

CWE

CWE-787 - Out-of-bounds Write
CWE-284 - Improper Access Control

Assigner

php mitre root

References

12 references

URL	Tags
https://bugs.php.net/bug.php?id=81026	x_refsource_MISC
https://www.debian.org/security/2021/dsa-4992	vendor-advisoryx_refsource_DEBIAN
https://www.debian.org/security/2021/dsa-4993	vendor-advisoryx_refsource_DEBIAN
http://www.openwall.com/lists/oss-security/2021/10/26/7	mailing-listx_refsource_MLIST
https://lists.debian.org/debian-lts-announce/2021…	mailing-listx_refsource_MLIST
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://lists.fedoraproject.org/archives/list/pac…	vendor-advisoryx_refsource_FEDORA
https://www.oracle.com/security-alerts/cpujan2022.html	x_refsource_MISC
https://security.netapp.com/advisory/ntap-2021111…	x_refsource_CONFIRM
https://www.oracle.com/security-alerts/cpuapr2022.html	x_refsource_MISC
https://security.gentoo.org/glsa/202209-20	vendor-advisoryx_refsource_GENTOO

Impacted products

1 product

Vendor	Product	Version
PHP Group	PHP	Affected: 7.3.x , ≤ 7.3.31 (custom) Affected: 7.4.x , < 7.4.25 (custom) Affected: 8.0.X , < 8.0.12 (custom)

Date Public

2021-10-18 00:00

Credits

Reported by Charles Fol

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T18:23:29.478Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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          {
            "tags": [
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            "url": "https://bugs.php.net/bug.php?id=81026"
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            "tags": [
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              "x_transferred"
            ],
            "url": "https://www.debian.org/security/2021/dsa-4993"
          },
          {
            "name": "[oss-security] 20211026 CVE-2021-21703: PHP-FPM 5.3.7 \u003c= 8.0.12 Local Root",
            "tags": [
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            "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/"
          },
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            "name": "FEDORA-2021-4140b54de2",
            "tags": [
              "vendor-advisory",
              "x_refsource_FEDORA",
              "x_transferred"
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            "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/"
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          {
            "name": "FEDORA-2021-02d218c3be",
            "tags": [
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            "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/"
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          {
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            "url": "https://www.oracle.com/security-alerts/cpujan2022.html"
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          },
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            "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
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              "x_transferred"
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            "url": "https://security.gentoo.org/glsa/202209-20"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "PHP",
          "vendor": "PHP Group",
          "versions": [
            {
              "lessThanOrEqual": "7.3.31",
              "status": "affected",
              "version": "7.3.x",
              "versionType": "custom"
            },
            {
              "lessThan": "7.4.25",
              "status": "affected",
              "version": "7.4.x",
              "versionType": "custom"
            },
            {
              "lessThan": "8.0.12",
              "status": "affected",
              "version": "8.0.X",
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            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "PHP FPM is being used with the main process having higher privileges than the worker processes."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Reported by Charles Fol"
        }
      ],
      "datePublic": "2021-10-18T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-787",
              "description": "CWE-787 Out-of-bounds Write",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "CWE-284 Improper Access Control",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2022-09-29T16:06:50.000Z",
        "orgId": "dd77f84a-d19a-4638-8c3d-a322d820ed2b",
        "shortName": "php"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://bugs.php.net/bug.php?id=81026"
        },
        {
          "name": "DSA-4992",
          "tags": [
            "vendor-advisory",
            "x_refsource_DEBIAN"
          ],
          "url": "https://www.debian.org/security/2021/dsa-4992"
        },
        {
          "name": "DSA-4993",
          "tags": [
            "vendor-advisory",
            "x_refsource_DEBIAN"
          ],
          "url": "https://www.debian.org/security/2021/dsa-4993"
        },
        {
          "name": "[oss-security] 20211026 CVE-2021-21703: PHP-FPM 5.3.7 \u003c= 8.0.12 Local Root",
          "tags": [
            "mailing-list",
            "x_refsource_MLIST"
          ],
          "url": "http://www.openwall.com/lists/oss-security/2021/10/26/7"
        },
        {
          "name": "[debian-lts-announce] 20211027 [SECURITY] [DLA 2794-1] php7.0 security update",
          "tags": [
            "mailing-list",
            "x_refsource_MLIST"
          ],
          "url": "https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html"
        },
        {
          "name": "FEDORA-2021-9f68f5f752",
          "tags": [
            "vendor-advisory",
            "x_refsource_FEDORA"
          ],
          "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/"
        },
        {
          "name": "FEDORA-2021-4140b54de2",
          "tags": [
            "vendor-advisory",
            "x_refsource_FEDORA"
          ],
          "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/"
        },
        {
          "name": "FEDORA-2021-02d218c3be",
          "tags": [
            "vendor-advisory",
            "x_refsource_FEDORA"
          ],
          "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.oracle.com/security-alerts/cpujan2022.html"
        },
        {
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://security.netapp.com/advisory/ntap-20211118-0003/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
        },
        {
          "name": "GLSA-202209-20",
          "tags": [
            "vendor-advisory",
            "x_refsource_GENTOO"
          ],
          "url": "https://security.gentoo.org/glsa/202209-20"
        }
      ],
      "source": {
        "defect": [
          "https://bugs.php.net/bug.php?id=81026"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "PHP-FPM memory access in root process leading to privilege escalation",
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      },
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security@php.net",
          "DATE_PUBLIC": "2021-10-18T22:40:00.000Z",
          "ID": "CVE-2021-21703",
          "STATE": "PUBLIC",
          "TITLE": "PHP-FPM memory access in root process leading to privilege escalation"
        },
        "affects": {
          "vendor": {
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              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "PHP",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c=",
                            "version_name": "7.3.x",
                            "version_value": "7.3.31"
                          },
                          {
                            "version_affected": "\u003c",
                            "version_name": "7.4.x",
                            "version_value": "7.4.25"
                          },
                          {
                            "version_affected": "\u003c",
                            "version_name": "8.0.X",
                            "version_value": "8.0.12"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "PHP Group"
              }
            ]
          }
        },
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            "lang": "en",
            "value": "PHP FPM is being used with the main process having higher privileges than the worker processes."
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          ]
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            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
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                  "value": "CWE-787 Out-of-bounds Write"
                }
              ]
            },
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "CWE-284 Improper Access Control"
                }
              ]
            }
          ]
        },
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            {
              "name": "https://bugs.php.net/bug.php?id=81026",
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            },
            {
              "name": "DSA-4992",
              "refsource": "DEBIAN",
              "url": "https://www.debian.org/security/2021/dsa-4992"
            },
            {
              "name": "DSA-4993",
              "refsource": "DEBIAN",
              "url": "https://www.debian.org/security/2021/dsa-4993"
            },
            {
              "name": "[oss-security] 20211026 CVE-2021-21703: PHP-FPM 5.3.7 \u003c= 8.0.12 Local Root",
              "refsource": "MLIST",
              "url": "http://www.openwall.com/lists/oss-security/2021/10/26/7"
            },
            {
              "name": "[debian-lts-announce] 20211027 [SECURITY] [DLA 2794-1] php7.0 security update",
              "refsource": "MLIST",
              "url": "https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html"
            },
            {
              "name": "FEDORA-2021-9f68f5f752",
              "refsource": "FEDORA",
              "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/"
            },
            {
              "name": "FEDORA-2021-4140b54de2",
              "refsource": "FEDORA",
              "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/"
            },
            {
              "name": "FEDORA-2021-02d218c3be",
              "refsource": "FEDORA",
              "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/"
            },
            {
              "name": "https://www.oracle.com/security-alerts/cpujan2022.html",
              "refsource": "MISC",
              "url": "https://www.oracle.com/security-alerts/cpujan2022.html"
            },
            {
              "name": "https://security.netapp.com/advisory/ntap-20211118-0003/",
              "refsource": "CONFIRM",
              "url": "https://security.netapp.com/advisory/ntap-20211118-0003/"
            },
            {
              "name": "https://www.oracle.com/security-alerts/cpuapr2022.html",
              "refsource": "MISC",
              "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
            },
            {
              "name": "GLSA-202209-20",
              "refsource": "GENTOO",
              "url": "https://security.gentoo.org/glsa/202209-20"
            }
          ]
        },
        "source": {
          "defect": [
            "https://bugs.php.net/bug.php?id=81026"
          ],
          "discovery": "EXTERNAL"
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "dd77f84a-d19a-4638-8c3d-a322d820ed2b",
    "assignerShortName": "php",
    "cveId": "CVE-2021-21703",
    "datePublished": "2021-10-25T05:40:08.576Z",
    "dateReserved": "2021-01-04T00:00:00.000Z",
    "dateUpdated": "2024-09-17T03:02:55.020Z",
    "state": "PUBLISHED"
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.