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2 vulnerabilities found for Tinyproxy by Tinyproxy Project

CVE-2026-31842 (GCVE-0-2026-31842)

Vulnerability from nvd – Published: 2026-04-07 11:17 – Updated: 2026-04-07 16:30
VLAI?
Title
Tinyproxy HTTP request parsing desynchronization via case-sensitive Transfer-Encoding handling
Summary
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.
Severity ?
8.7 (High)
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
https://github.com/tinyproxy/tinyproxy/issues/604 issue-trackingtechnical-descriptionthird-party-advisory
https://github.com/tinyproxy/tinyproxy product
https://datatracker.ietf.org/doc/html/rfc7230 technical-description
Impacted products
Vendor Product Version
Tinyproxy Project Tinyproxy Affected: 0 , ≤ 1.11.3 (custom)
Create a notification for this product.
Credits
Muxammadiyev G'iyosiddin
Show details on NVD website
To clipboard 

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CVE-2026-31842 (GCVE-0-2026-31842)

Vulnerability from cvelistv5 – Published: 2026-04-07 11:17 – Updated: 2026-04-07 16:30
VLAI?
Title
Tinyproxy HTTP request parsing desynchronization via case-sensitive Transfer-Encoding handling
Summary
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.
Severity ?
8.7 (High)
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
https://github.com/tinyproxy/tinyproxy/issues/604 issue-trackingtechnical-descriptionthird-party-advisory
https://github.com/tinyproxy/tinyproxy product
https://datatracker.ietf.org/doc/html/rfc7230 technical-description
Impacted products
Vendor Product Version
Tinyproxy Project Tinyproxy Affected: 0 , ≤ 1.11.3 (custom)
Create a notification for this product.
Credits
Muxammadiyev G'iyosiddin
Show details on NVD website
To clipboard 

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