{"id":"CVE-2025-55702","state":"PUBLISHED","title":"Apache Traffic Server: An unread Expect: 100-continue request body is framed as a new request","description":"When a client sends a POST with Expect: 100-continue and the origin answers before reading the body, Apache Traffic Server parses the unread body left on the client connection as the next request. An attacker behind a front-end proxy that shares connections to Traffic Server can use this to smuggle requests past the front end and desynchronize responses for other users.\n\n\n\nThis issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.\n\n\n\nUsers are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.","publishedAt":"2026-10-21T18:24:21.377Z","updatedAt":"2026-10-23T11:06:22.172Z","severity":{"score":7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N","source":"apache"},"assigner":"apache","products":["Apache Software Foundation Apache Traffic Server"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache Traffic Server","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThanOrEqual":"8.1.11","versionType":"semver"},{"version":"9.0.0","status":"affected","lessThanOrEqual":"9.2.15","versionType":"semver"},{"version":"10.0.0","status":"affected","lessThanOrEqual":"10.1.4","versionType":"semver"},{"version":"10.2.0","status":"affected","versionType":"semver"}]}],"references":["https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc"],"weaknesses":["CWE-444"],"ingestedAt":"2026-10-29T20:09:31.862Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/55xxx/CVE-2025-55702.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-55702","state":"PUBLISHED","datePublished":"2026-10-21T18:24:21.377Z","dateUpdated":"2026-10-23T11:06:22.172Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2025-08-13T22:27:49.065Z"},"containers":{"cna":{"title":"Apache Traffic Server: An unread Expect: 100-continue request body is framed as a new request","descriptions":[{"lang":"en","value":"When a client sends a POST with Expect: 100-continue and the origin answers before reading the body, Apache Traffic Server parses the unread body left on the client connection as the next request. An attacker behind a front-end proxy that shares connections to Traffic Server can use this to smuggle requests past the front end and desynchronize responses for other users.\n\n\n\nThis issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.\n\n\n\nUsers are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue."}],"affected":[{"vendor":"Apache Software Foundation","product":"Apache Traffic Server","defaultStatus":"unaffected","versions":[{"version":"8.0.0","status":"affected","lessThanOrEqual":"8.1.11","versionType":"semver"},{"version":"9.0.0","status":"affected","lessThanOrEqual":"9.2.15","versionType":"semver"},{"version":"10.0.0","status":"affected","lessThanOrEqual":"10.1.4","versionType":"semver"},{"version":"10.2.0","status":"affected","versionType":"semver"}]}],"references":[{"url":"https://lists.apache.org/thread/r95dq29ywcd1f4x30snxlqmb12z4s4kc","tags":["vendor-advisory"]}],"metrics":[{"other":{"type":"Textual description of severity","content":{"text":"important"}},"scenarios":[{"lang":"en","value":"GENERAL"}]},{"scenarios":[{"lang":"en","value":"GENERAL"}],"format":"CVSS","cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE","baseSeverity":"HIGH","baseScore":8.7,"vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N"}},{"scenarios":[{"lang":"en","value":"GENERAL"}],"format":"CVSS","cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","subConfidentialityImpact":"HIGH","vulnIntegrityImpact":"NONE","subIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"HIGH","baseScore":7,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-444","description":"CWE-444 Inconsistent Interpretation of HTTP Requests","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"apache","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateUpdated":"2026-10-21T18:24:21.377Z"},"source":{"discovery":"UNKNOWN"},"credits":[{"lang":"en","value":"Sebastiano Sartor","type":"reporter"}],"x_generator":{"engine":"scripts/cve_render.py"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2025-55702","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-22T23:05:04.402377Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-23T11:06:22.172Z"}}]}}}