CVE-2026-15685: ollama Improper Validation of Array Index

Vulnerability summary

CVE-2026-15685 is a high (CVSS 7.5) Improper Validation of Array Index vulnerability in ollama. EPSS estimates a 0.71% chance of exploitation in the next 30 days, higher than 53.1% of scored vulnerabilities.

Timeline

1. 13-07-2026
   PublishedVulnerability first disclosed.
2. 14-07-2026
   Last modifiedVulnerability information updated.

Description

Ollama downloadBlob Improper Validation of Array Index Denial-of-Service Vulnerability. This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of Ollama. Authentication is not required to exploit this vulnerability. The specific flaw exists within the downloadBlob function. The issue results from the lack of proper validation of user-supplied data, which can result in a memory access past the end of an allocated array. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-27277.

• CWE-129Improper Validation of Array IndexThe product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.