{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-97688","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-09-24T21:43:37.208Z","datePublished":"2026-09-29T15:32:17.622Z","dateUpdated":"2026-09-29T15:42:34.502Z"},"containers":{"cna":{"title":"urllib3: Chunked Deflate streaming can enter an infinite loop","problemTypes":[{"descriptions":[{"cweId":"CWE-835","lang":"en","description":"CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6.9,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/urllib3/urllib3/security/advisories/GHSA-gh4c-6fx4-qh6g","tags":["x_refsource_CONFIRM"],"url":"https://github.com/urllib3/urllib3/security/advisories/GHSA-gh4c-6fx4-qh6g"},{"name":"https://github.com/urllib3/urllib3/commit/ea2ad7b21a80da3632f80016526a18864586077f","tags":["x_refsource_MISC"],"url":"https://github.com/urllib3/urllib3/commit/ea2ad7b21a80da3632f80016526a18864586077f"},{"name":"https://github.com/urllib3/urllib3/releases/tag/2.8.0","tags":["x_refsource_MISC"],"url":"https://github.com/urllib3/urllib3/releases/tag/2.8.0"}],"affected":[{"vendor":"urllib3","product":"urllib3","versions":[{"version":">= 2.6.2, < 2.8.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-09-29T15:32:17.622Z"},"descriptions":[{"lang":"en","value":"urllib3 is an HTTP client library for Python. From 2.6.2 until 2.8.0, HTTPResponse.stream and HTTPResponse.read_chunked can enter an infinite loop because the Deflate decoder retains trailing bytes as unconsumed input after reaching end-of-stream and repeatedly decodes them without progress. The issue occurs when an untrusted server sends a chunked Deflate response whose decoded body exceeds a positive finite chunk size and whose encoded body has trailing bytes, specifically a response with Transfer-Encoding: chunked and Content-Encoding: deflate, content decoding enabled, and the positive finite amt=N streaming chunk size. The attack mechanism is that a malicious server returns a compressed chunked response with trailing bytes after the Deflate stream. The impact is excessive CPU usage and a request that does not complete, and network read timeouts do not interrupt the loop because no further socket read occurs. This issue is fixed in version 2.8.0."}],"source":{"advisory":"GHSA-gh4c-6fx4-qh6g","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-29T15:42:28.931695Z","id":"CVE-2026-97688","options":[{"Exploitation":"none"},{"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":"2026-09-29T15:42:34.502Z"}}]}}