SB2021101243 - Multiple vulnerabilities in Adobe Acrobat and Reader

Description

This security bulletin contains information about 4 vulnerabilities.

1) Use-after-free (CVE-ID: CVE-2021-40728)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing PDF files. A remote attacker can create a specially crafted PDF file, trick the victim into opening it, trigger a use-after-free error and execute arbitrary code on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

2) Out-of-bounds read (CVE-ID: CVE-2021-40729)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition. A remote attacker can create a specially crafted PDF file, trick the victim into opening it, trigger out-of-bounds read error and read contents of memory on the system.

3) Use-after-free (CVE-ID: CVE-2021-40730)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to a use-after-free error when processing JPG2000 images inside a PDF files. A remote attacker can create a specially crafted PDF file, trick the victim into opening it, trigger a use-after-free error and read contents of memory on the system.

4) Out-of-bounds write (CVE-ID: CVE-2021-40731)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing JPG2000 images inside a PDF file. A remote attacker can create a specially crafted PDF file, trick the victim into opening it using the affected software, trigger an out-of-bounds write and execute arbitrary code on the target system.

Remediation

Install update from vendor's website.

References

• https://helpx.adobe.com/security/products/acrobat/apsb21-104.html
• https://www.zerodayinitiative.com/advisories/ZDI-21-1162/
• https://www.zerodayinitiative.com/advisories/ZDI-21-1163/