CVE-2020-11538: 
Python vulnerability analysis and mitigation

CVE-2020-11538 affects Pillow through version 7.0.0, discovered and disclosed in April 2020. The vulnerability involves multiple out-of-bounds reads in the parsing of SGI image files within the libImaging/SgiRleDecode.c component, which is distinct from the previously identified CVE-2020-5311 (NVD).

The vulnerability has been assigned a CVSS v3.1 Base Score of 8.1 (High), with the vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. The issue specifically occurs in the SGI-RLE decoding functionality within libImaging/SgiRleDecode.c, where multiple out-of-bounds read operations can be triggered when processing specially crafted SGI image files (Ubuntu, Pillow Docs).

If exploited, this vulnerability could allow an attacker to cause a denial of service condition or potentially execute arbitrary code through specially crafted SGI image files. The high CVSS score indicates potential impacts on confidentiality, integrity, and availability of the affected system (NVD).

The vulnerability requires no privileges or user interaction to exploit, though it does have high attack complexity. The attack vector is network-accessible, meaning it can be exploited remotely (Ubuntu).

The vulnerability was fixed in Pillow version 7.1.0. Users are advised to upgrade to this version or later. Various Linux distributions have also released patches for their packaged versions: Ubuntu 20.04 LTS (7.0.0-4ubuntu0.1), Ubuntu 18.04 LTS (5.1.0-1ubuntu0.3), and Fedora has also issued fixes for versions 31 and 32 (USN-4430-1, USN-4430-2).