CVE-2020-26535: 
Foxit PDF Reader vulnerability analysis and mitigation

An issue was discovered in Foxit Reader and PhantomPDF before 10.1. If TslAlloc attempts to allocate thread local storage but obtains an unacceptable index value, V8 throws an exception that leads to a write access violation (and read access violation) (NVD, CVE).

The vulnerability has been assigned a CVSS v3.1 Base Score of 9.8 CRITICAL with vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. The vulnerability is classified as an Out-of-bounds Write (CWE-787) issue that occurs during thread local storage allocation (NVD).

The vulnerability allows attackers to potentially execute remote code through write and read access violations. Given the CVSS score of 9.8, this represents a critical security risk with potential for complete system compromise (NVD).

The vulnerability was addressed in Foxit Reader and PhantomPDF version 10.1. Users should upgrade to this version or later to mitigate the security risk (Foxit Security Bulletin).

The vulnerability was reported through Trend Micro's Zero Day Initiative (ZDI) and was considered a high-severity issue. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) included this vulnerability in their vulnerability summary bulletin with a CVSS score of 7.5 (SecurityWeek).