CVE-2026-31842

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.

CVSS v3 7.5 HIGH
CVSS v2.0 7.8 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

7.8^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:N/I:N/A:C

Exploitability : 10.0 / Impact : 6.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact COMPLETE

References

Link	Resource
https://datatracker.ietf.org/doc/html/rfc7230	Exploit Technical Description
https://github.com/tinyproxy/tinyproxy	Product
https://github.com/tinyproxy/tinyproxy/issues/604	Exploit Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:tinyproxy_project:tinyproxy:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-07 12:16

Updated : 2026-08-10 12:17

NVD link : CVE-2026-31842

Mitre link : CVE-2026-31842

CVE.ORG link : CVE-2026-31842

JSON object : View

Products Affected

tinyproxy_project

tinyproxy

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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