CVE-2026-103262: Tornadoweb Tornado

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

Tornado versions before 6.5.9 contain an unbounded memory accumulation vulnerability in CurlAsyncHTTPClient that allows remote attackers to cause denial of service by sending a compressed response. Attackers can send a gzip-encoded decompression bomb that accumulates in memory without size limits, causing the application process to be killed by out-of-memory conditions.

Affected products

• Tornadoweb Tornado: before 6.5.9 (fixed in 6.5.9)

Published 2026-10-01. Last modified 2026-10-06.