Amazon Linux AMI update for php7-pear

1) Deserialization of Untrusted Data

EUVDB-ID: #VU48669

Risk: High

CVSSv3.1: 8.8 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2020-28948

CWE-ID: CWE-502 - Deserialization of Untrusted Data

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to insecure input validation when processing serialized data, related to case sensitivity issues (e.g. "phar:" protocol is blocked, however  "PHAR:" is not). A remote attacker can pass specially crafted data to the application and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Update the affected packages:

noarch:
    php7-pear-1.10.12-4.30.amzn1.noarch

src:
    php7-pear-1.10.12-4.30.amzn1.src

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1466.html

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. However, proof of concept for this vulnerability is available.

2) Input validation error

EUVDB-ID: #VU48668

Risk: High

CVSSv3.1: 9.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C]

CVE-ID: CVE-2020-28949

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to improper sanitization of the user-supplied input when processing URI handlers in filenames. A remote attacker can pass the "file://" string in the filename and overwrite arbitrary files on the system.

Mitigation

Update the affected packages:

noarch:
    php7-pear-1.10.12-4.30.amzn1.noarch

src:
    php7-pear-1.10.12-4.30.amzn1.src

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1466.html

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?

Yes. This vulnerability is being exploited in the wild.