CWE-444
- 25
- vulnerabilities tracked
- 1
- under active exploitation
- 12
- critical
- 2 September 2026
- latest publication
cve
Vulnerability watch
idvulnerabilityseveritypublished
CVE-2026-48710Kludex Starlette HTTP Request/Response Smuggling VulnerabilityKludex Starlette Critical CVE-2026-63382Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, the libevent evhttp parser in http.c inconsistently handles duplicate Transfer-Encoding headers, comma-separated Transfer-Encoding values, and bare line feeds in chunked framing. evhttp_find_header can select only the first header, evhttp_check_transfer_encoding_ was absent so the previous whole-string comparison fails to recognize valid lists ending in chunked, and evhttp_handle_chunked_read uses EVBUFFER_EOL_CRLF rather than EVBUFFER_EOL_CRLF_STRICT, accepting bare LF chunk terminators. When libevent is deployed behind a proxy that frames the same request differently, an unauthenticated remote attacker can desynchronize request boundaries and smuggle a second request, potentially bypassing access controls or poisoning caches. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.NVD analysis in progress Critical CVSS 9.2 CVE-2026-63385Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has two HTTP parsing weaknesses in http.c. evhttp_decode_uri_internal decodes percent-encoded %00 bytes into literal NUL characters, which can cause downstream C string operations to truncate a path and bypass validation performed on a different representation. evhttp_header_is_valid_value also accepts obsolete line folding in header values containing carriage return or line feed characters, allowing a proxy and libevent to interpret headers differently and enabling header injection or access control bypass. The CRLF header acceptance is fixed in versions 2.1.13 and 2.2.2-alpha, but the reviewed patches do not clearly remediate the URI NUL-truncation condition.NVD analysis in progress Critical CVSS 9.2 CVE-2026-73256Mongoose is an embedded web server and network library. Prior to 7.22, a remote unauthenticated attacker can exploit an HTTP/1.0 reverse-proxy deployment by sending a request with Transfer-Encoding: chunked and conflicting framing. The http_cb() function in src/http.c tests hm.proto.len with an impossible greater-than-eight condition even though mg_http_parse() requires an eight-byte protocol string, so is_http_1_0 is never set. Mongoose consequently processes chunked encoding that an HTTP/1.0 proxy can ignore, enabling request smuggling and unauthorized access or state changes. This issue is fixed in version 7.22.NVD analysis in progress Critical CVSS 9.1 CVE-2026-73257Mongoose is an embedded web server and network library. Priro to version 7.22, a remote unauthenticated attacker can send an HTTP request containing both Content-Length and Transfer-Encoding: chunked. The cl_count and te_count checks in the mg_http_parse() and http_cb() paths in src/http.c accept both headers and prioritize chunked encoding, while a Content-Length-preferring reverse proxy can use a different request boundary. This CL.TE desynchronization can inject requests that access or modify resources in another user context. This issue is fixed in version 7.22.NVD analysis in progress Critical CVSS 9.1 CVE-2026-65370ServiceTalk HTTP/1.x incorrectly handles malformed Transfer-Encoding which could result in request smuggling attacks. This vulnerability is addressed in servicetalk version 0.42.65.NVD analysis in progress High CVSS 7.5 CVE-2026-73495blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. Prior to 0.23.18 and 1.0.0-M42, blaze-server can merge HTTP/1.1 chunked-body trailer fields into Request.headers. Because trailer fields are attacker-controlled, an unauthenticated remote client can inject arbitrary header names and values, including X-Forwarded-For and internal authorization headers, that a fronting proxy sanitized from the request-header section, bypassing header-based trust decisions in the application. Any http4s application using BlazeServerBuilder over HTTP/1.1 whose routes or middleware trust proxy-set headers, including X-Forwarded-For, X-Real-IP, and X-Forwarded-Host, is affected. If a fronting proxy strips or normalizes those headers but forwards chunked bodies with trailers intact, an attacker can spoof client IP for allow-lists, rate limits, or auditing, forge the https scheme, or inject internal authorization headers. A promoted Connection: close trailer is also honored, allowing attacker-controlled termination of pooled backend connections. This issue is fixed in versions 0.23.18 and 1.0.0-M42.NVD analysis in progress High CVSS 7.4 CVE-2026-71324Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.53, 3.6.24, and 3.7.9, Traefik's default HTTP reverse proxy forwards a plain HTTP/2 or HTTP/3 CONNECT request and its body to an HTTP/1.1 upstream through a shared net/http.Transport. When the upstream answers the CONNECT with a keep-alive non-2xx response and does not drain the body, Traefik returns the desynchronized backend socket to its shared pool and reuses it for other clients. An unauthenticated attacker can use this behavior to make a different client read the attacker's smuggled response, which can include authenticated or private content from another request. The ForwardAuth middleware with forwardBody true and preserveRequestMethod true can re-issue a CONNECT with the buffered body attached, exposing the auth-client pool to the same desynchronization. This issue is fixed in 2.11.53, 3.6.24, and 3.7.9.NVD analysis in progress High CVSS 7 CVE-2026-9190An HTTP request smuggling vulnerability in the HTTP App Server of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker to bypass authentication and authorization checks, hijack a legitimate user's session, or capture credentials. The vulnerability occurs when a crafted HTTP request containing both Content-Length and Transfer-Encoding headers causes a reverse proxy and MarkLogic Server to interpret request boundaries differently.NVD analysis in progress Critical CVSS 9.1 CVE-2026-57834Apache Traffic Server allows request smuggling if chunked messages are malformed.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.
Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.Apache Traffic Server Critical CVSS 10 CVE-2026-58150Apache Traffic Server does not reject Transfer-Encoding in HTTP/2 requests, allowing downgrade request smuggling.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.
Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.Apache Traffic Server Critical CVSS 10 CVE-2026-58153Apache Traffic Server forwards HTTP/2 origin trailers to HTTP/1 clients without proper chunked framing when converting HTTP/2 to HTTP/1.
This issue affects Apache Traffic Server: from 10.0.0 through 10.1.3.
Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.Apache Traffic Server High CVSS 8.3 CVE-2026-58155Apache Traffic Server truncates over-long header names, allowing header aliasing, request smuggling, and policy bypass.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.
Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.Apache Traffic Server Critical CVSS 9.3 CVE-2026-59898Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.Netty High CVSS 7.5 CVE-2026-15064IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.7 is vulnerable to HTTP Response Smuggling due to improper handling of non-standard HTTP version tokens.Ibm Websphere Application Server High CVSS 8.7 CVE-2026-15325IBM WebSphere Application Server and IBM WebSphere Application Server - Liberty is vulnerable to HTTP request smuggling due to improper handling of TRACE requests.Ibm Websphere Application Server High CVSS 8.7 CVE-2026-15328IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.7 is vulnerable to HTTP request smuggling.Ibm Websphere Application Server High CVSS 8.1 CVE-2026-67182Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to bypass access controls by injecting bare line feed characters (0x0A) into client-supplied request header values that are copied verbatim to upstream connections without validation. Attackers can craft a header value containing a complete additional HTTP request that is interpreted as a separate request by backends such as Go net/http and Python http.server, causing the backend to process a smuggled request with attacker-chosen method, path, and headers that bypasses the rouille handler's access control logic. High CVSS 7.5 CVE-2026-50197Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.26.10, zalando/skipper's OpenPolicyAgent integration silently bypasses request-body inspection on HTTP/1.1 Transfer-Encoding: chunked and HTTP/2 requests that omit the content-length pseudo-header, because the opaAuthorizeRequestWithBody filter and OpenPolicyAgentInstance.ExtractHttpBodyOptionally in filters/openpolicyagent/openpolicyagent.go produce an empty raw_body and input.parsed_body while the upstream service receives the full attacker-controlled body. This issue is fixed in version 0.26.10. High CVSS 7.8 CVE-2026-27690Due to an HTTP Request Smuggling vulnerability in SAP Approuter, an unauthenticated attacker could send a specially crafted HTTP request that leads to request-response desynchronization. This could result in the exposure of user responses and cause the system to become unavailable. This leads to a high impact on confidentiality and availability.NVD analysis in progress Critical CVSS 9.1 CVE-2025-3110OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP header values, allowing remote attackers to perform HTTP request smuggling when deployed behind a reverse proxyOpenvpn Openvpn Access Server High CVSS 7.5 CVE-2026-11541IBM WebSphere Application Server 9.0, and 8.5 and IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 are affected by an HTTP request smuggling vulnerability.Ibm Websphere Application Server Critical CVSS 9.8 CVE-2026-11806IBM WebSphere Application Server - Liberty 17.0.0.3 through 26.0.0.6 is affected by an arbitrary file read vulnerability with the restConnector-2.0 feature enabled.Ibm Websphere Application Server High CVSS 7.5 CVE-2026-13762Inconsistent interpretation of HTTP/2 requests in Amazon CloudFront with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body across frames so that only a partial body is inspected.
This issue was remediated server-side. No customer action is required.Amazon Cloudfront Critical CVSS 9.8 CVE-2026-13763Inconsistent interpretation of HTTP/2 requests in AWS Application Load Balancer with AWS WAF enabled might allow remote actors to bypass AWS WAF managed rule body inspection via crafted HTTP/2 requests that fragment the request body across frames so that only a partial body is inspected. This issue only impacts HTTP/2 ALB target groups.
To remediate this issue, customers should enable the "Inspect after sufficient data" target group configuration associated to an ALB load balancer. Refer to: ( https://docs.aws.amazon.com/elasticloadbalancing/latest/application/edit-target-group-attributes.html#waf-http2-inspection )Amazon Application Load Balancer Critical CVSS 9.8