A denial of service is possible from excessive resource consumption in net/http and mime/multipart. Multipart form parsing with mime/multipart.Reader.ReadForm can consume largely unlimited amounts of memory and disk files. This also affects form parsing in the net/http package with the Request methods FormFile, FormValue, ParseMultipartForm, and PostFormValue. ReadForm takes a maxMemory parameter, and is documented as storing "up to maxMemory bytes +10MB (reserved for non-file parts) in memory". File parts which cannot be stored in memory are stored on disk in temporary files. The unconfigurable 10MB reserved for non-file parts is excessively large and can potentially open a denial of service vector on its own. However, ReadForm did not properly account for all memory consumed by a parsed form, such as map entry overhead, part names, and MIME headers, permitting a maliciously crafted form to consume well over 10MB. In addition, ReadForm contained no limit on the number of disk files created, permitting a relatively small request body to create a large number of disk temporary files. With fix, ReadForm now properly accounts for various forms of memory overhead, and should now stay within its documented limit of 10MB + maxMemory bytes of memory consumption. Users should still be aware that this limit is high and may still be hazardous. In addition, ReadForm now creates at most one on-disk temporary file, combining multiple form parts into a single temporary file. The mime/multipart.File interface type's documentation states, "If stored on disk, the File's underlying concrete type will be an *os.File.". This is no longer the case when a form contains more than one file part, due to this coalescing of parts into a single file. The previous behavior of using distinct files for each form part may be reenabled with the environment variable GODEBUG=multipartfiles=distinct. Users should be aware that multipart.ReadForm and the http.Request methods that call it do not limit the amount of disk consumed by temporary files. Callers can limit the size of form data with http.MaxBytesReader.

In archive/zip in Go before 1.16.8 and 1.17.x before 1.17.1, a crafted archive header (falsely designating that many files are present) can cause a NewReader or OpenReader panic. NOTE: this issue exists because of an incomplete fix for CVE-2021-33196.

The processing time for parsing some invalid inputs scales non-linearly with respect to the size of the input. This affects programs which parse untrusted PEM inputs.

A malicious HTTP/2 client which rapidly creates requests and immediately resets them can cause excessive server resource consumption. While the total number of requests is bounded by the http2.Server.MaxConcurrentStreams setting, resetting an in-progress request allows the attacker to create a new request while the existing one is still executing. With the fix applied, HTTP/2 servers now bound the number of simultaneously executing handler goroutines to the stream concurrency limit (MaxConcurrentStreams). New requests arriving when at the limit (which can only happen after the client has reset an existing, in-flight request) will be queued until a handler exits. If the request queue grows too large, the server will terminate the connection. This issue is also fixed in golang.org/x/net/http2 for users manually configuring HTTP/2. The default stream concurrency limit is 250 streams (requests) per HTTP/2 connection. This value may be adjusted using the golang.org/x/net/http2 package; see the Server.MaxConcurrentStreams setting and the ConfigureServer function.

QUIC connections do not set an upper bound on the amount of data buffered when reading post-handshake messages, allowing a malicious QUIC connection to cause unbounded memory growth. With fix, connections now consistently reject messages larger than 65KiB in size.

Multipart form parsing can consume large amounts of CPU and memory when processing form inputs containing very large numbers of parts. This stems from several causes: 1. mime/multipart.Reader.ReadForm limits the total memory a parsed multipart form can consume. ReadForm can undercount the amount of memory consumed, leading it to accept larger inputs than intended. 2. Limiting total memory does not account for increased pressure on the garbage collector from large numbers of small allocations in forms with many parts. 3. ReadForm can allocate a large number of short-lived buffers, further increasing pressure on the garbage collector. The combination of these factors can permit an attacker to cause an program that parses multipart forms to consume large amounts of CPU and memory, potentially resulting in a denial of service. This affects programs that use mime/multipart.Reader.ReadForm, as well as form parsing in the net/http package with the Request methods FormFile, FormValue, ParseMultipartForm, and PostFormValue. With fix, ReadForm now does a better job of estimating the memory consumption of parsed forms, and performs many fewer short-lived allocations. In addition, the fixed mime/multipart.Reader imposes the following limits on the size of parsed forms: 1. Forms parsed with ReadForm may contain no more than 1000 parts. This limit may be adjusted with the environment variable GODEBUG=multipartmaxparts=. 2. Form parts parsed with NextPart and NextRawPart may contain no more than 10,000 header fields. In addition, forms parsed with ReadForm may contain no more than 10,000 header fields across all parts. This limit may be adjusted with the environment variable GODEBUG=multipartmaxheaders=.

Reader.Read does not set a limit on the maximum size of file headers. A maliciously crafted archive could cause Read to allocate unbounded amounts of memory, potentially causing resource exhaustion or panics. After fix, Reader.Read limits the maximum size of header blocks to 1 MiB.

Go before 1.12.16 and 1.13.x before 1.13.7 (and the crypto/cryptobyte package before 0.0.0-20200124225646-8b5121be2f68 for Go) allows attacks on clients (resulting in a panic) via a malformed X.509 certificate.

Calling Parse on a "// +build" build tag line with deeply nested expressions can cause a panic due to stack exhaustion.

Calling Decoder.Decode on a message which contains deeply nested structures can cause a panic due to stack exhaustion. This is a follow-up to CVE-2022-30635.

The net/http HTTP/1.1 client mishandled the case where a server responds to a request with an "Expect: 100-continue" header with a non-informational (200 or higher) status. This mishandling could leave a client connection in an invalid state, where the next request sent on the connection will fail. An attacker sending a request to a net/http/httputil.ReverseProxy proxy can exploit this mishandling to cause a denial of service by sending "Expect: 100-continue" requests which elicit a non-informational response from the backend. Each such request leaves the proxy with an invalid connection, and causes one subsequent request using that connection to fail.

The protojson.Unmarshal function can enter an infinite loop when unmarshaling certain forms of invalid JSON. This condition can occur when unmarshaling into a message which contains a google.protobuf.Any value, or when the UnmarshalOptions.DiscardUnknown option is set.

A request smuggling attack is possible when using MaxBytesHandler. When using MaxBytesHandler, the body of an HTTP request is not fully consumed. When the server attempts to read HTTP2 frames from the connection, it will instead be reading the body of the HTTP request, which could be attacker-manipulated to represent arbitrary HTTP2 requests.

A too-short encoded message can cause a panic in Float.GobDecode and Rat GobDecode in math/big in Go before 1.17.13 and 1.18.5, potentially allowing a denial of service.

An attacker may cause a denial of service by crafting an Accept-Language header which ParseAcceptLanguage will take significant time to parse.

Uncontrolled recursion in Reader.Read in compress/gzip before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via an archive containing a large number of concatenated 0-length compressed files.

Infinite loop in Read in crypto/rand before Go 1.17.11 and Go 1.18.3 on Windows allows attacker to cause an indefinite hang by passing a buffer larger than 1 << 32 - 1 bytes.

Uncontrolled recursion in Unmarshal in encoding/xml before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via unmarshalling an XML document into a Go struct which has a nested field that uses the 'any' field tag.

Uncontrolled recursion in Glob in path/filepath before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via a path containing a large number of path separators.

Uncontrolled recursion in Glob in io/fs before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via a path which contains a large number of path separators.

Uncontrolled recursion in Decoder.Decode in encoding/gob before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via a message which contains deeply nested structures.

Go before 1.12.11 and 1.3.x before 1.13.2 can panic upon an attempt to process network traffic containing an invalid DSA public key. There are several attack scenarios, such as traffic from a client to a server that verifies client certificates.

In net/http in Go before 1.18.6 and 1.19.x before 1.19.1, attackers can cause a denial of service because an HTTP/2 connection can hang during closing if shutdown were preempted by a fatal error.

Uncontrolled recursion in Decoder.Skip in encoding/xml before Go 1.17.12 and Go 1.18.4 allows an attacker to cause a panic due to stack exhaustion via a deeply nested XML document.

In x/text in Go 1.15.4, an "index out of range" panic occurs in language.ParseAcceptLanguage while parsing the -u- extension. (x/text/language is supposed to be able to parse an HTTP Accept-Language header.)

encoding/pem in Go before 1.17.9 and 1.18.x before 1.18.1 has a Decode stack overflow via a large amount of PEM data.

regexp.Compile in Go before 1.16.15 and 1.17.x before 1.17.8 allows stack exhaustion via a deeply nested expression.

In x/text in Go before v0.3.5, a "slice bounds out of range" panic occurs in language.ParseAcceptLanguage while processing a BCP 47 tag. (x/text/language is supposed to be able to parse an HTTP Accept-Language header.)

A nil pointer dereference in the golang.org/x/crypto/ssh component through v0.0.0-20201203163018-be400aefbc4c for Go allows remote attackers to cause a denial of service against SSH servers.

Rat.SetString in math/big in Go before 1.16.14 and 1.17.x before 1.17.7 has an overflow that can lead to Uncontrolled Memory Consumption.

Go before 1.16.10 and 1.17.x before 1.17.3 allows an archive/zip Reader.Open panic via a crafted ZIP archive containing an invalid name or an empty filename field.

net/http in Go before 1.16.12 and 1.17.x before 1.17.5 allows uncontrolled memory consumption in the header canonicalization cache via HTTP/2 requests.

golang.org/x/text/language in golang.org/x/text before 0.3.7 can panic with an out-of-bounds read during BCP 47 language tag parsing. Index calculation is mishandled. If parsing untrusted user input, this can be used as a vector for a denial-of-service attack.

In archive/zip in Go before 1.15.13 and 1.16.x before 1.16.5, a crafted file count (in an archive's header) can cause a NewReader or OpenReader panic.

golang.org/x/net before v0.0.0-20210520170846-37e1c6afe023 allows attackers to cause a denial of service (infinite loop) via crafted ParseFragment input.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <math><template><mn><b></template>, leading to a "panic: runtime error" (index out of range) in (*insertionModeStack).pop in node.go, called from inHeadIM, during an html.Parse call.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <svg><template><desc><t><svg></template>, leading to a "panic: runtime error" (index out of range) in (*nodeStack).pop in node.go, called from (*parser).clearActiveFormattingElements, during an html.Parse call.

The html package (aka x/net/html) through 2018-09-17 in Go mishandles <math><template><mo><template>, leading to a "panic: runtime error" in parseCurrentToken in parse.go during an html.Parse call.

The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server.

ImportedSymbols in debug/macho (for Open or OpenFat) in Go before 1.16.10 and 1.17.x before 1.17.3 Accesses a Memory Location After the End of a Buffer, aka an out-of-bounds slice situation.

Go before 1.14.12 and 1.15.x before 1.15.4 allows Denial of Service.

The ParseAddress function constructs domain-literal address components through repeated string concatenation. When parsing large domain-literal components, this can cause excessive CPU consumption.

Within HostnameError.Error(), when constructing an error string, there is no limit to the number of hosts that will be printed out. Furthermore, the error string is constructed by repeated string concatenation, leading to quadratic runtime. Therefore, a certificate provided by a malicious actor can result in excessive resource consumption.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <table><math><select><mi><select></table>, leading to an infinite loop during an html.Parse call because inSelectIM and inSelectInTableIM do not comply with a specification.

The html package (aka x/net/html) through 2018-09-17 in Go mishandles <template><tBody><isindex/action=0>, leading to a "panic: runtime error" in inBodyIM in parse.go during an html.Parse call.

The html package (aka x/net/html) before 2018-07-13 in Go mishandles "in frameset" insertion mode, leading to a "panic: runtime error" for html.Parse of <template><object>, <template><applet>, or <template><marquee>. This is related to HTMLTreeBuilder.cpp in WebKit.

Due to the design of the name constraint checking algorithm, the processing time of some inputs scale non-linearly with respect to the size of the certificate. This affects programs which validate arbitrary certificate chains.

Validating certificate chains which contain DSA public keys can cause programs to panic, due to a interface cast that assumes they implement the Equal method. This affects programs which validate arbitrary certificate chains.

In Go before 1.15.13 and 1.16.x before 1.16.5, there can be a panic for a large exponent to the math/big.Rat SetString or UnmarshalText method.

Go before 1.13.15 and 14.x before 1.14.7 can have an infinite read loop in ReadUvarint and ReadVarint in encoding/binary via invalid inputs.