{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:11",
        "name": "tinyproxy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "tinyproxy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "tinyproxy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "tinyproxy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer() function uses strcmp() to compare the header value against \"chunked\", even though RFC 7230 specifies that transfer-coding names are case-insensitive. By sending a request with Transfer-Encoding: Chunked, an unauthenticated remote attacker can cause Tinyproxy to misinterpret the request as having no body. In this state, Tinyproxy sets content_length.client to -1, skips pull_client_data_chunked(), forwards request headers upstream, and transitions into relay_connection() raw TCP forwarding while unread body data remains buffered. This leads to inconsistent request state between Tinyproxy and backend servers. RFC-compliant backends (e.g., Node.js, Nginx) will continue waiting for chunked body data, causing connections to hang indefinitely. This behavior enables application-level denial of service through backend worker exhaustion. Additionally, in deployments where Tinyproxy is used for request-body inspection, filtering, or security enforcement, the unread body may be forwarded without proper inspection, resulting in potential security control bypass.",
  "id": "DEBIAN-CVE-2026-31842",
  "modified": "2026-04-28T19:53:21.025967016Z",
  "published": "2026-04-07T12:16:21.040Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-31842"
    }
  ],
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ],
  "upstream": [
    "CVE-2026-31842"
  ]
}