Red Hat Enterprise Linux 8 update for the php:7.4 module
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2021-21705 CVE-2021-21703 |
| CWE-ID | CWE-918 CWE-787 |
| Exploitation vector | Network |
| Public exploit | Public exploit code for vulnerability #2 is available. |
| Vulnerable software Subscribe |
Red Hat Enterprise Linux for ARM 64 Operating systems & Components / Operating system Red Hat Enterprise Linux for Power, little endian Operating systems & Components / Operating system Red Hat Enterprise Linux for IBM z Systems Operating systems & Components / Operating system Red Hat Enterprise Linux for x86_64 Operating systems & Components / Operating system |
| Vendor | Red Hat Inc. |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Server-Side Request Forgery (SSRF)
EUVDB-ID: #VU54565
Risk: Medium
CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]
CVE-ID: CVE-2021-21705
CWE-ID:
CWE-918 - Server-Side Request Forgery (SSRF)
Exploit availability: No
DescriptionThe disclosed vulnerability allows a remote attacker to perform SSRF attacks.
The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can send a specially crafted HTTP request, bypass the FILTER_VALIDATE_URL and trick the application to initiate requests to arbitrary systems.
Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.
MitigationInstall updates from vendor's website.
Red Hat Enterprise Linux for ARM 64: 8
Red Hat Enterprise Linux for Power, little endian: 8
Red Hat Enterprise Linux for IBM z Systems: 8
Red Hat Enterprise Linux for x86_64: 8.0
External linkshttp://access.redhat.com/errata/RHSA-2022:1935
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Out-of-bounds write
EUVDB-ID: #VU57656
Risk: Low
CVSSv3.1: 7.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C]
CVE-ID: CVE-2021-21703
CWE-ID:
CWE-787 - Out-of-bounds write
Exploit availability: No
DescriptionThe vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists in the way PHP handles shared memory access, when using PHP FPM SAPI with main FPM daemon process running as root and child worker processes running as lower-privileged users. A child process can access shared memory with the main process and write to it. As a result, it is possible to cause the root process to conduct invalid memory reads and writes with root privileges. A local user can trigger an out-of-bounds write error and execute arbitrary code on the system with root privileges.
Install updates from vendor's website.
Red Hat Enterprise Linux for ARM 64: 8
Red Hat Enterprise Linux for Power, little endian: 8
Red Hat Enterprise Linux for IBM z Systems: 8
Red Hat Enterprise Linux for x86_64: 8.0
External linkshttp://access.redhat.com/errata/RHSA-2022:1935
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.
