Search vulnerabilities

Use the Query Builder to create your own search query, or check out the documentation to learn the search syntax.

Results 57

Export CSV
CVE-2026-111943

Distrust compromised intermediate certificates in crypto/x509

On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in crypto/x509 to return an error when calling Verify with any of the known intermediate certificates that are no longer considered to be trustworthy.

CVSS 3.1 · 6.8 Medium EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Redhat
Products
Crypto/x509 Enterprise Linux Hummingbird
CVE-2026-97032

HTTP/2 server crash due to HPACK encoder race in net/http

HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http2
CVE-2026-97030

Recognize yield as regexp preceder keyword in html/template

A trusted template author may have previously written a valid template wherein the use of the 'yield' keyword would not be correctly escaped. We now ensure that valid keyword uses are escaped and non-keyword uses are not escaped.

CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Html/template
CVE-2026-94448

Reset context tracking on consecutive template expressions in html/template

When a JavaScript template literal contains consecutive expressions, the context tracking state was not properly reset upon entering a new expression. We now ensure that template-literal expression entries correctly reset context variables so all subsequent regular expression literals are accurately recognized and escaped.

CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Html/template
CVE-2026-94440

Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart

Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Mime/multipart Net/textproto
CVE-2026-78660

HTTP/2 transport accepts malformed framing-related headers in net/http

Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http2
CVE-2026-78659

HTTP/2 server memory exhaustion due to Trailer headers in net/http

When "Trailer" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a "Trailer" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http2
CVE-2026-94439

HTTP/1 server connection desynchronization after 2xx CONNECT response in net/http

When an HTTP server handler sends a 2xx response to an HTTP/1 CONNECT request and returns without hijacking the connection, the server improperly continues to read and serve requests from the connection. Since a 2xx response to an HTTP/1 CONNECT converts the connection into a tunnel, the server should not treat the connection as continuing to contain HTTP. The impact of this misbehavior is mostly limited to potential request smuggling, where an intermediate proxy considers the data on the connection to be tunneled and the server considers it to be HTTP.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http
CVE-2026-78669

Excessive CPU consumption from repeated initial window changes in net/http

A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http2
CVE-2026-78667

Lack of limit on size of parsed Range headers in net/http

When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http
CVE-2026-78663

Double flow control refund on HTTP/2 server streams in net/http

The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.

CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http2
CVE-2026-97031

Reject malformed ECH outer extension references in crypto/tls

Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references. We now reject these as malformed and curb the memory amplification vector as a result.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Crypto Tls
CVE-2026-56866

HTTP/1 client connection desynchronization after CONNECT rejection in net/http

When http.Transport sends an HTTP/1 CONNECT request with a non-empty Request.Body, it writes the body directly to the connection without framing after the request headers. If the server rejects the CONNECT request with a non-2xx keep-alive response, Transport returns the connection to the idle pool. Because CONNECT requests do not have a request body, the server may interpret the trailing body bytes as a subsequent pipelined HTTP/1.1 request on the connection, leaving the pooled connection desynchronized and causing the next caller that reuses it to read the response to the injected request. In reverse proxies (including httputil.ReverseProxy) that forward CONNECT requests through a shared Transport, this can lead to cross-user response poisoning.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Net/http Net/http/httputil
CVE-2026-56857

Root.Mkdir(All) can follow junctions out of the root on Windows in os

On Windows, when the target of Root.Mkdir or Root.MkdirAll is a junction pointing to an empty location, the operation can create a directory at the junction target even when that target is located outside the root. This only applies to operations where the last path component is a junction (path/to/junction, but not path/junction/target).

CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Internal/syscall/windows Os
CVE-2026-42499

Quadratic string concatenation in consumePhrase in net/mail

Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Golang
Products
Net\/mail Go
CVE-2026-39820

Quadratic string concatentation in consumeComment in net/mail

Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Golang
Products
Net/mail Go
CVE-2026-33810

Case-sensitive excludedSubtrees name constraints cause Auth Bypass in crypto/x509

When verifying a certificate chain containing excluded DNS constraints, these constraints are not correctly applied to wildcard DNS SANs which use a different case than the constraint. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Golang
Products
Crypto/x509 Go
CVE-2026-32283

Unauthenticated TLS 1.3 KeyUpdate record can cause persistent connection retention and DoS in crypto/tls

If one side of the TLS connection sends multiple key update messages post-handshake in a single record, the connection can deadlock, causing uncontrolled consumption of resources. This can lead to a denial of service. This only affects TLS 1.3.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Golang
Products
Crypto Tls Go
CVE-2026-32280

Unexpected work during chain building in crypto/x509

During chain building, the amount of work that is done is not correctly limited when a large number of intermediate certificates are passed in VerifyOptions.Intermediates, which can lead to a denial of service. This affects both direct users of crypto/x509 and users of crypto/tls.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Vendors
Go Standard Library Golang
Products
Crypto/x509 Go
CVE-2026-27145

Inefficient candidate hostname parsing in crypto/x509

(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries. This caused strings.Split(host, ".") to execute repeatedly on the same input hostname. With a large DNS SAN list, verification costs scaled quadratically based on the number of SAN entries multiplied by the hostname's label count. Because x509.Verify validates hostnames before building the certificate chain, this overhead occurred even for untrusted certificates.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed
Vendors
Go Standard Library
Products
Crypto/x509