{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-9375","assignerOrgId":"c09c270a-b464-47c1-9133-acb35b22c19a","state":"PUBLISHED","assignerShortName":"@huntr_ai","dateReserved":"2026-05-23T14:33:21.716Z","datePublished":"2026-06-19T18:45:10.409Z","dateUpdated":"2026-06-22T15:53:30.194Z"},"containers":{"cna":{"title":"Decompression Bomb Bypass via Negative max_length in Streaming API in urllib3","providerMetadata":{"orgId":"c09c270a-b464-47c1-9133-acb35b22c19a","shortName":"@huntr_ai","dateUpdated":"2026-06-19T18:45:10.409Z"},"descriptions":[{"lang":"en","value":"urllib3 version 2.6.3 is vulnerable to a decompression bomb bypass in its streaming API (`preload_content=False`) when using Brotli support. The issue arises due to three independent code paths in `response.py` that bypass the `max_length` protection introduced in version 2.6.0 to mitigate CVE-2025-66471. Specifically, negative `max_length` values can be produced due to buffer arithmetic in `read()`, `flush_decoder` unconditionally overrides `max_length` to `-1`, and `_flush_decoder()` passes no limit at all, defaulting to unlimited decompression. This allows a malicious HTTP server to trigger an out-of-memory (OOM) condition by decompressing large payloads into memory, leading to a denial of service (DoS). The vulnerability affects urllib3 2.6.3 and Brotli 1.2.0 and impacts applications and libraries using `requests` or `urllib3` to stream content from untrusted sources."}],"affected":[{"vendor":"urllib3","product":"urllib3/urllib3","versions":[{"version":"unspecified","lessThan":"2.7.0","status":"affected","versionType":"custom"}]}],"references":[{"url":"https://huntr.com/bounties/ddd09eb9-b87d-4a43-84df-48837b1bbc23"},{"url":"https://github.com/urllib3/urllib3/commit/2bdcc44d1e163fb5cc48a8662425e35e15adfe6a"}],"metrics":[{"cvssV3_0":{"version":"3.0","attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"type":"CWE","lang":"en","description":"CWE-400 Uncontrolled Resource Consumption","cweId":"CWE-400"}]}],"source":{"advisory":"ddd09eb9-b87d-4a43-84df-48837b1bbc23","discovery":"EXTERNAL"}},"adp":[{"references":[{"url":"https://huntr.com/bounties/ddd09eb9-b87d-4a43-84df-48837b1bbc23","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-22T15:53:04.589743Z","id":"CVE-2026-9375","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-22T15:53:30.194Z"}}]}}