7.8
HIGH
CVE-2021-21703
Apache PHP Memory Corruption Bug
Description

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.

INFO

Published Date :

Oct. 25, 2021, 6:15 a.m.

Last Modified :

Nov. 7, 2023, 3:30 a.m.

Source :

[email protected]

Remotely Exploitable :

No

Impact Score :

6.0

Exploitability Score :

1.1
Public PoC/Exploit Available at Github

CVE-2021-21703 has a 1 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2021-21703 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Fedoraproject fedora
1 Debian debian_linux
1 Netapp clustered_data_ontap
1 Php php
1 Oracle communications_diameter_signaling_router
: Total Affected Vendor : 5 | Products : 5
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-21703.

URL Resource
http://www.openwall.com/lists/oss-security/2021/10/26/7 Mailing List Patch Third Party Advisory
https://bugs.php.net/bug.php?id=81026 Exploit Issue Tracking Patch Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/
https://security.gentoo.org/glsa/202209-20 Third Party Advisory
https://security.netapp.com/advisory/ntap-20211118-0003/ Third Party Advisory
https://www.debian.org/security/2021/dsa-4992 Third Party Advisory
https://www.debian.org/security/2021/dsa-4993 Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html Patch Vendor Advisory
https://www.oracle.com/security-alerts/cpujan2022.html Patch Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Profile Photo
Henzau/WEB-NMAP

Internship research project about website API and packages weakness

Python

Updated: 11 months, 2 weeks ago
1 stars 0 fork 0 watcher
Born at : April 18, 2023, 5:05 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-21703 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-21703 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference PHP Group https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/ [No types assigned]
    Added Reference PHP Group https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/ [No types assigned]
    Added Reference PHP Group https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ [No types assigned]
    Removed Reference PHP Group https://lists.fedoraproject.org/archives/list/[email protected]/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/
    Removed Reference PHP Group https://lists.fedoraproject.org/archives/list/[email protected]/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/
    Removed Reference PHP Group https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/
  • Modified Analysis by [email protected]

    Oct. 29, 2022

    Action Type Old Value New Value
    Changed Reference Type https://security.gentoo.org/glsa/202209-20 No Types Assigned https://security.gentoo.org/glsa/202209-20 Third Party Advisory
  • CVE Modified by [email protected]

    Sep. 29, 2022

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/202209-20 [No Types Assigned]
  • Modified Analysis by [email protected]

    Apr. 28, 2022

    Action Type Old Value New Value
    Changed Reference Type https://www.oracle.com/security-alerts/cpuapr2022.html No Types Assigned https://www.oracle.com/security-alerts/cpuapr2022.html Patch, Vendor Advisory
  • CVE Modified by [email protected]

    Apr. 20, 2022

    Action Type Old Value New Value
    Added Reference https://www.oracle.com/security-alerts/cpuapr2022.html [No Types Assigned]
  • Modified Analysis by [email protected]

    Feb. 22, 2022

    Action Type Old Value New Value
    Changed Reference Type https://www.oracle.com/security-alerts/cpujan2022.html No Types Assigned https://www.oracle.com/security-alerts/cpujan2022.html Patch, Vendor Advisory
    Added CPE Configuration OR *cpe:2.3:a:oracle:communications_diameter_signaling_router:*:*:*:*:*:*:*:* versions from (including) 8.0.0.0 up to (including) 8.5.0.2
  • CVE Modified by [email protected]

    Feb. 07, 2022

    Action Type Old Value New Value
    Added Reference https://www.oracle.com/security-alerts/cpujan2022.html [No Types Assigned]
  • Modified Analysis by [email protected]

    Nov. 28, 2021

    Action Type Old Value New Value
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ Mailing List, Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20211118-0003/ No Types Assigned https://security.netapp.com/advisory/ntap-20211118-0003/ Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 18, 2021

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20211118-0003/ [No Types Assigned]
  • CVE Modified by [email protected]

    Nov. 17, 2021

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ [No Types Assigned]
  • CVE Modified by [email protected]

    Nov. 10, 2021

    Action Type Old Value New Value
    Removed Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ [Mailing List, Third Party Advisory]
  • Reanalysis by [email protected]

    Nov. 04, 2021

    Action Type Old Value New Value
    Changed Reference Type http://www.openwall.com/lists/oss-security/2021/10/26/7 Mailing List, Third Party Advisory http://www.openwall.com/lists/oss-security/2021/10/26/7 Mailing List, Patch, Third Party Advisory
    Changed Reference Type https://bugs.php.net/bug.php?id=81026 Exploit, Vendor Advisory https://bugs.php.net/bug.php?id=81026 Exploit, Issue Tracking, Patch, Vendor Advisory
    Changed CPE Configuration OR *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.3.0 up to (including) 7.3.31 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.4.0 up to (including) 7.4.25 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 8.0.0 up to (including) 8.0.12 OR *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.3.0 up to (including) 7.3.31 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.4.0 up to (excluding) 7.4.25 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 8.0.0 up to (excluding) 8.0.12
  • Modified Analysis by [email protected]

    Nov. 03, 2021

    Action Type Old Value New Value
    Removed CVSS V2 NIST (AV:L/AC:L/Au:N/C:C/I:C/A:C)
    Added CVSS V2 NIST (AV:L/AC:M/Au:N/C:C/I:C/A:C)
    Removed CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CVSS V3.1 NIST AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/ Mailing List, Third Party Advisory
    Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Nov. 03, 2021

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/6PZVLICZUJMXOGWOUWSBAEGIVTF6Y6V3/ [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 28, 2021

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/PBM3KKB3RY2YPOKNMC4HIH7IH3T3WC74/ [No Types Assigned]
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/JO5RA6YOBGGGKLIA6F6BQRZDDECF5L3R/ [No Types Assigned]
  • Initial Analysis by [email protected]

    Oct. 28, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:L/AC:L/Au:N/C:C/I:C/A:C)
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type http://www.openwall.com/lists/oss-security/2021/10/26/7 No Types Assigned http://www.openwall.com/lists/oss-security/2021/10/26/7 Mailing List, Third Party Advisory
    Changed Reference Type https://bugs.php.net/bug.php?id=81026 No Types Assigned https://bugs.php.net/bug.php?id=81026 Exploit, Vendor Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html No Types Assigned https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html Mailing List, Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2021/dsa-4992 No Types Assigned https://www.debian.org/security/2021/dsa-4992 Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2021/dsa-4993 No Types Assigned https://www.debian.org/security/2021/dsa-4993 Third Party Advisory
    Added CWE NIST CWE-787
    Added CPE Configuration OR *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.3.0 up to (including) 7.3.31 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 7.4.0 up to (including) 7.4.25 *cpe:2.3:a:php:php:*:*:*:*:*:*:*:* versions from (including) 8.0.0 up to (including) 8.0.12
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Oct. 27, 2021

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2021/10/msg00021.html [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 26, 2021

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2021/10/26/7 [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 26, 2021

    Action Type Old Value New Value
    Added Reference https://www.debian.org/security/2021/dsa-4993 [No Types Assigned]
    Added Reference https://www.debian.org/security/2021/dsa-4992 [No Types Assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-21703 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-21703 weaknesses.

CAPEC-19: Embedding Scripts within Scripts Embedding Scripts within Scripts CAPEC-441: Malicious Logic Insertion Malicious Logic Insertion CAPEC-478: Modification of Windows Service Configuration Modification of Windows Service Configuration CAPEC-479: Malicious Root Certificate Malicious Root Certificate CAPEC-502: Intent Spoof Intent Spoof CAPEC-503: WebView Exposure WebView Exposure CAPEC-536: Data Injected During Configuration Data Injected During Configuration CAPEC-546: Incomplete Data Deletion in a Multi-Tenant Environment Incomplete Data Deletion in a Multi-Tenant Environment CAPEC-550: Install New Service Install New Service CAPEC-551: Modify Existing Service Modify Existing Service CAPEC-552: Install Rootkit Install Rootkit CAPEC-556: Replace File Extension Handlers Replace File Extension Handlers CAPEC-558: Replace Trusted Executable Replace Trusted Executable CAPEC-562: Modify Shared File Modify Shared File CAPEC-563: Add Malicious File to Shared Webroot Add Malicious File to Shared Webroot CAPEC-564: Run Software at Logon Run Software at Logon CAPEC-578: Disable Security Software Disable Security Software
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.15 }} 0.03%

score

0.49758

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
: