CWE-113
Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
Description
The product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers.
Hierarchy (View 1000)
Related attack patterns (CAPEC)
CAPEC-105 · CAPEC-31 · CAPEC-34 · CAPEC-85
CVEs mapped to this weakness (131)
page 5 of 7| CVE | Vendor / Product | Sev | Risk | CVSS | EPSS | KEV | Published | Description |
|---|---|---|---|---|---|---|---|---|
| CVE-2025-0588 | Med | 0.32 | 4.9 | 0.00 | Feb 11, 2025 | In affected versions of Octopus Server it was possible for a user with sufficient access to set custom headers in all server responses. By submitting a specifically crafted referrer header the user could ensure that all subsequent server responses would return 500 errors… | ||
| CVE-2026-44214 | Med | 0.31 | 5.8 | 0.00 | May 26, 2026 | eventsource-encoder encodes events as well-formed EventSource/Server Sent Event (SSE) messages. Prior to 1.0.2, eventsource-encoder does not sanitize the event or id fields of an EventSourceMessage before serializing them. An attacker who controls either field can inject… | ||
| CVE-2026-34767 | Med | 0.31 | 5.9 | 0.00 | Apr 4, 2026 | Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.3, 40.8.3, and 41.0.3, apps that register custom protocol handlers via protocol.handle() / protocol.registerSchemesAsPrivileged() or modify… | ||
| CVE-2022-20772 | Med | 0.31 | 4.7 | 0.01 | Nov 4, 2022 | A vulnerability in Cisco Email Security Appliance (ESA) and Cisco Secure Email and Web Manager could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack. This vulnerability is due to the failure of the application or its environment to… | ||
| CVE-2022-37953 | Med | 0.31 | 4.7 | 0.00 | Aug 25, 2022 | An HTTP response splitting vulnerability exists in the AM Gateway Challenge-Response dialog of WorkstationST (<v07.09.15) and could allow an attacker to compromise a victim's browser/session. WorkstationST is only deployed in specific, controlled environments rendering attack… | ||
| CVE-2020-3117 | Med | 0.31 | 4.7 | 0.01 | Sep 23, 2020 | A vulnerability in the API Framework of Cisco AsyncOS for Cisco Web Security Appliance (WSA) and Cisco Content Security Management Appliance (SMA) could allow an unauthenticated, remote attacker to inject crafted HTTP headers in the web server's response. The vulnerability is… | ||
| CVE-2026-91991 | Med | 0.28 | 5.4 | 0.00 | Sep 15, 2026 | Tornado before 6.5.8 contains an incomplete fix for cookie attribute injection that allows attackers to inject arbitrary cookie attributes by passing capitalized or legacy keyword arguments to set_cookie. Attackers can embed semicolon-delimited data in capitalized parameters… | ||
| CVE-2024-58384 | Med | 0.28 | 5.4 | 0.00 | Sep 15, 2026 | Tornado before 6.4.1 contains a CRLF injection vulnerability in CurlAsyncHTTPClient that fails to reject carriage return and line feed characters in request headers. Attackers can inject CRLF sequences into header values to inject arbitrary headers or construct entirely new HTTP… | ||
| CVE-2026-29086 | Med | 0.28 | 5.4 | 0.00 | Mar 4, 2026 | Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.12.4, the setCookie() utility did not validate semicolons (;), carriage returns (\r), or newline characters (\n) in the domain and path options when constructing the… | ||
| CVE-2025-42934 | Med | 0.28 | 4.3 | 0.00 | Aug 12, 2025 | SAP S/4HANA Supplier invoice is vulnerable to CRLF Injection. An attacker with user-level privileges can bypass the allowlist and insert untrusted sites into the 'Trusted Sites' configuration by injecting line feed (LF) characters into application inputs. This vulnerability has… | ||
| CVE-2026-77341 | Med | 0.27 | — | 0.00 | Aug 28, 2026 | cpp-httplib is a C++ header-only HTTP/HTTPS library. In version 0.49.0, the chunked-response trailer output path writes trailer header names and values directly to the socket without validating them, allowing CRLF sequences in a trailer field to inject additional headers or… | ||
| CVE-2026-64785 | Med | 0.27 | 5.3 | 0.00 | Jul 23, 2026 | SwiftNIO HTTP/2 was missing validation on inbound HEADERS frames that let CR, LF, NUL, SP and other control characters reach an HTTP/1.1 backend through NIOHTTP2's HTTP/2-to-HTTP/1 codec, enabling HTTP request smuggling or response splitting. This vulnerability is addressed in… | ||
| CVE-2026-49214 | Med | 0.27 | 5.3 | 0.00 | Jun 11, 2026 | guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 did not reject ASCII control characters, whitespace, or DEL in first-party URI host components. A vulnerable flow is: First, an application accepts a user-controlled URL. Second, the… | ||
| CVE-2026-43966 | Med | 0.27 | 5.3 | 0.00 | Jun 8, 2026 | Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in ninenines cowlib allows HTTP response splitting via non-VCHAR bytes in structured-fields string values. cow_http_struct_hd:escape_string/2 in cowlib only escapes \ and… | ||
| CVE-2026-38978 | Med | 0.27 | 5.3 | 0.00 | Jun 2, 2026 | transmission through 4.1.1 was found to have a clickjacking weakness in the browser-facing WebUI and RPC response paths. | ||
| CVE-2026-34715 | Med | 0.27 | 5.3 | 0.00 | Apr 2, 2026 | ewe is a Gleam web server. Prior to version 3.0.6, the encode_headers function in src/ewe/internal/encoder.gleam directly interpolates response header keys and values into raw HTTP bytes without validating or stripping CRLF (\r\n) sequences. An application that passes… | ||
| CVE-2026-34519 | Med | 0.27 | 5.3 | 0.00 | Apr 1, 2026 | AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the reason parameter when creating a Response may be able to inject extra headers or similar exploits. This issue has been patched in version 3.13.4. | ||
| CVE-2026-34514 | Med | 0.27 | 5.3 | 0.00 | Apr 1, 2026 | AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4. | ||
| CVE-2026-24489 | Med | 0.27 | 5.3 | 0.00 | Jan 27, 2026 | Gakido is a Python HTTP client focused on browser impersonation and anti-bot evasion. A vulnerability was discovered in Gakido prior to version 0.1.1 that allowed HTTP header injection through CRLF (Carriage Return Line Feed) sequences in user-supplied header values and names.… | ||
| CVE-2026-22779 | Med | 0.27 | 5.3 | 0.00 | Jan 14, 2026 | BlackSheep is an asynchronous web framework to build event based web applications with Python. Prior to 2.4.6, the HTTP Client implementation in BlackSheep is vulnerable to CRLF injection. Missing headers validation makes it possible for an attacker to modify the HTTP requests… |
- risk 0.32cvss 4.9epss 0.00
In affected versions of Octopus Server it was possible for a user with sufficient access to set custom headers in all server responses. By submitting a specifically crafted referrer header the user could ensure that all subsequent server responses would return 500 errors…
- risk 0.31cvss 5.8epss 0.00
eventsource-encoder encodes events as well-formed EventSource/Server Sent Event (SSE) messages. Prior to 1.0.2, eventsource-encoder does not sanitize the event or id fields of an EventSourceMessage before serializing them. An attacker who controls either field can inject…
- risk 0.31cvss 5.9epss 0.00
Electron is a framework for writing cross-platform desktop applications using JavaScript, HTML and CSS. Prior to versions 38.8.6, 39.8.3, 40.8.3, and 41.0.3, apps that register custom protocol handlers via protocol.handle() / protocol.registerSchemesAsPrivileged() or modify…
- risk 0.31cvss 4.7epss 0.01
A vulnerability in Cisco Email Security Appliance (ESA) and Cisco Secure Email and Web Manager could allow an unauthenticated, remote attacker to conduct an HTTP response splitting attack. This vulnerability is due to the failure of the application or its environment to…
- risk 0.31cvss 4.7epss 0.00
An HTTP response splitting vulnerability exists in the AM Gateway Challenge-Response dialog of WorkstationST (<v07.09.15) and could allow an attacker to compromise a victim's browser/session. WorkstationST is only deployed in specific, controlled environments rendering attack…
- risk 0.31cvss 4.7epss 0.01
A vulnerability in the API Framework of Cisco AsyncOS for Cisco Web Security Appliance (WSA) and Cisco Content Security Management Appliance (SMA) could allow an unauthenticated, remote attacker to inject crafted HTTP headers in the web server's response. The vulnerability is…
- risk 0.28cvss 5.4epss 0.00
Tornado before 6.5.8 contains an incomplete fix for cookie attribute injection that allows attackers to inject arbitrary cookie attributes by passing capitalized or legacy keyword arguments to set_cookie. Attackers can embed semicolon-delimited data in capitalized parameters…
- risk 0.28cvss 5.4epss 0.00
Tornado before 6.4.1 contains a CRLF injection vulnerability in CurlAsyncHTTPClient that fails to reject carriage return and line feed characters in request headers. Attackers can inject CRLF sequences into header values to inject arbitrary headers or construct entirely new HTTP…
- risk 0.28cvss 5.4epss 0.00
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.12.4, the setCookie() utility did not validate semicolons (;), carriage returns (\r), or newline characters (\n) in the domain and path options when constructing the…
- risk 0.28cvss 4.3epss 0.00
SAP S/4HANA Supplier invoice is vulnerable to CRLF Injection. An attacker with user-level privileges can bypass the allowlist and insert untrusted sites into the 'Trusted Sites' configuration by injecting line feed (LF) characters into application inputs. This vulnerability has…
- risk 0.27cvss —epss 0.00
cpp-httplib is a C++ header-only HTTP/HTTPS library. In version 0.49.0, the chunked-response trailer output path writes trailer header names and values directly to the socket without validating them, allowing CRLF sequences in a trailer field to inject additional headers or…
- risk 0.27cvss 5.3epss 0.00
SwiftNIO HTTP/2 was missing validation on inbound HEADERS frames that let CR, LF, NUL, SP and other control characters reach an HTTP/1.1 backend through NIOHTTP2's HTTP/2-to-HTTP/1 codec, enabling HTTP request smuggling or response splitting. This vulnerability is addressed in…
- risk 0.27cvss 5.3epss 0.00
guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 did not reject ASCII control characters, whitespace, or DEL in first-party URI host components. A vulnerable flow is: First, an application accepts a user-controlled URL. Second, the…
- risk 0.27cvss 5.3epss 0.00
Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting') vulnerability in ninenines cowlib allows HTTP response splitting via non-VCHAR bytes in structured-fields string values. cow_http_struct_hd:escape_string/2 in cowlib only escapes \ and…
- risk 0.27cvss 5.3epss 0.00
transmission through 4.1.1 was found to have a clickjacking weakness in the browser-facing WebUI and RPC response paths.
- risk 0.27cvss 5.3epss 0.00
ewe is a Gleam web server. Prior to version 3.0.6, the encode_headers function in src/ewe/internal/encoder.gleam directly interpolates response header keys and values into raw HTTP bytes without validating or stripping CRLF (\r\n) sequences. An application that passes…
- risk 0.27cvss 5.3epss 0.00
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the reason parameter when creating a Response may be able to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.
- risk 0.27cvss 5.3epss 0.00
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.
- risk 0.27cvss 5.3epss 0.00
Gakido is a Python HTTP client focused on browser impersonation and anti-bot evasion. A vulnerability was discovered in Gakido prior to version 0.1.1 that allowed HTTP header injection through CRLF (Carriage Return Line Feed) sequences in user-supplied header values and names.…
- risk 0.27cvss 5.3epss 0.00
BlackSheep is an asynchronous web framework to build event based web applications with Python. Prior to 2.4.6, the HTTP Client implementation in BlackSheep is vulnerable to CRLF injection. Missing headers validation makes it possible for an attacker to modify the HTTP requests…