CVE-2020-11538 : Security Advisory and Response

In libImaging/SgiRleDecode.c in Pillow through 7.0.0, a number of out-of-bounds reads exist in the parsing of SGI image files, a different issue than CVE-2020-5311.

Understanding CVE-2020-11538

What is CVE-2020-11538?

CVE-2020-11538 is a vulnerability found in Pillow through version 7.0.0, specifically in the parsing of SGI image files, leading to out-of-bounds reads.

The Impact of CVE-2020-11538

This vulnerability could potentially allow attackers to execute arbitrary code or cause a denial of service by exploiting the out-of-bounds read issue.

Technical Details of CVE-2020-11538

Vulnerability Description

The vulnerability exists in the parsing of SGI image files in libImaging/SgiRleDecode.c in Pillow through version 7.0.0, resulting in multiple out-of-bounds reads.

Affected Systems and Versions

Product: Not applicable
Vendor: Not applicable
Versions affected: Not applicable

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting a malicious SGI image file to trigger the out-of-bounds read, potentially leading to arbitrary code execution or denial of service.

Mitigation and Prevention

Immediate Steps to Take

Update Pillow to version 7.1.0 or later to mitigate the vulnerability.
Avoid opening untrusted SGI image files until the software is patched.

Long-Term Security Practices

Regularly update software and libraries to the latest versions to address known vulnerabilities.
Implement proper input validation and boundary checks in image processing functions to prevent similar issues.

Patching and Updates

Ensure that all systems running Pillow are updated to version 7.1.0 or above to patch the vulnerability.