Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an HTTPServer configured with decompress_request=True to consume effectively unlimited memory. This issue is fixed in version 6.5.6.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| tornadoweb | tornado | affected |
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Project Subscriptions
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Advisories
| Source | ID | Title |
|---|---|---|
 Github GHSA |
GHSA-mgf9-4vpg-hj56 | tornado AsyncHTTPClient accumulates decompressed chunks without size limit (gzip bomb) |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 14 Jul 2026 21:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an HTTPServer configured with decompress_request=True to consume effectively unlimited memory. This issue is fixed in version 6.5.6. | |
| Title | tornado AsyncHTTPClient accumulates decompressed chunks without size limit (gzip bomb) | |
| Weaknesses | CWE-409 | |
| References |
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| Metrics |
cvssV3_1
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Projects
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MITRE
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-07-14T20:45:02.982Z
Reserved: 2026-06-01T22:03:19.640Z
Link: CVE-2026-49855
Vulnrichment
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NVD
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Redhat
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OpenCVE Enrichment
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Weaknesses