Harrison Green

**Name of the Vulnerable Software and Affected Versions** HTSlib versions prior to 1.23.1 HTSlib version 1.22.2 HTSlib version 1.21.1 **Description** HTSlib is a library used for reading and writing bioinformatics file formats. A heap buffer overflow can occur in the BGZF index file reader due to an integer overflow in the `bgzf index load hfile()` function. This overflow leads to an undersized buffer allocation, and subsequent writes to this buffer can cause a crash or overwrite heap structures. Exploitation may lead to arbitrary code execution if a user opens a specially crafted file. **Recommendations** Versions prior to 1.23.1: Update to version 1.23.1 or later. Version 1.22.2: Update to version 1.23.1 or later. Version 1.21.1: Update to version 1.23.1 or later. Discard any `.gzi` index files from untrusted sources. Recreate index files using the `bgzip -r` option.