CVE-2026-103262

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tornadoweb/tornado/commit/e412435febba4569c552c5c9054f1bf92bd171a9
https://github.com/tornadoweb/tornado/security/advisories/GHSA-chx6-46f5-w4vp
https://www.vulncheck.com/advisories/tornado-before-6.5.9-denial-of-service-via-curlasynchttpclient
https://github.com/tornadoweb/tornado/security/advisories/GHSA-chx6-46f5-w4vp

Configurations

No configuration.

History

06 Oct 2026, 01:16

Type	Values Removed	Values Added
References	~~() https://github.com/tornadoweb/tornado/security/advisories/GHSA-chx6-46f5-w4vp -~~	() https://github.com/tornadoweb/tornado/security/advisories/GHSA-chx6-46f5-w4vp -

01 Oct 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-01 11:17

Updated : 2026-10-06 01:16

NVD link : CVE-2026-103262

Mitre link : CVE-2026-103262

CVE.ORG link : CVE-2026-103262

JSON object : View

Products Affected

No product.

CWE

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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