GLSA-202311-09 : Go: Multiple Vulnerabilities

critical Nessus Plugin ID 186294

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Description

The remote host is affected by the vulnerability described in GLSA-202311-09 (Go: Multiple Vulnerabilities)

- 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. (CVE-2022-2879)

- Requests forwarded by ReverseProxy include the raw query parameters from the inbound request, including unparsable parameters rejected by net/http. This could permit query parameter smuggling when a Go proxy forwards a parameter with an unparsable value. After fix, ReverseProxy sanitizes the query parameters in the forwarded query when the outbound request's Form field is set after the ReverseProxy. Director function returns, indicating that the proxy has parsed the query parameters. Proxies which do not parse query parameters continue to forward the original query parameters unchanged. (CVE-2022-2880)

- Programs which compile regular expressions from untrusted sources may be vulnerable to memory exhaustion or denial of service. The parsed regexp representation is linear in the size of the input, but in some cases the constant factor can be as high as 40,000, making relatively small regexps consume much larger amounts of memory. After fix, each regexp being parsed is limited to a 256 MB memory footprint. Regular expressions whose representation would use more space than that are rejected. Normal use of regular expressions is unaffected. (CVE-2022-41715)

- An attacker can cause excessive memory growth in a Go server accepting HTTP/2 requests. HTTP/2 server connections contain a cache of HTTP header keys sent by the client. While the total number of entries in this cache is capped, an attacker sending very large keys can cause the server to allocate approximately 64 MiB per open connection. (CVE-2022-41717)

- A maliciously crafted HTTP/2 stream could cause excessive CPU consumption in the HPACK decoder, sufficient to cause a denial of service from a small number of small requests. (CVE-2022-41723)

- Large handshake records may cause panics in crypto/tls. Both clients and servers may send large TLS handshake records which cause servers and clients, respectively, to panic when attempting to construct responses. This affects all TLS 1.3 clients, TLS 1.2 clients which explicitly enable session resumption (by setting Config.ClientSessionCache to a non-nil value), and TLS 1.3 servers which request client certificates (by setting Config.ClientAuth >= RequestClientCert). (CVE-2022-41724)

- 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. (CVE-2022-41725)

- HTTP and MIME header parsing can allocate large amounts of memory, even when parsing small inputs, potentially leading to a denial of service. Certain unusual patterns of input data can cause the common function used to parse HTTP and MIME headers to allocate substantially more memory than required to hold the parsed headers. An attacker can exploit this behavior to cause an HTTP server to allocate large amounts of memory from a small request, potentially leading to memory exhaustion and a denial of service.
With fix, header parsing now correctly allocates only the memory required to hold parsed headers.
(CVE-2023-24534)

- 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=. (CVE-2023-24536)

- Calling any of the Parse functions on Go source code which contains //line directives with very large line numbers can cause an infinite loop due to integer overflow. (CVE-2023-24537)

- Templates do not properly consider backticks (`) as Javascript string delimiters, and do not escape them as expected. Backticks are used, since ES6, for JS template literals. If a template contains a Go template action within a Javascript template literal, the contents of the action can be used to terminate the literal, injecting arbitrary Javascript code into the Go template. As ES6 template literals are rather complex, and themselves can do string interpolation, the decision was made to simply disallow Go template actions from being used inside of them (e.g. var a = {{.}}), since there is no obviously safe way to allow this behavior. This takes the same approach as github.com/google/safehtml. With fix, Template.Parse returns an Error when it encounters templates like this, with an ErrorCode of value 12. This ErrorCode is currently unexported, but will be exported in the release of Go 1.21. Users who rely on the previous behavior can re-enable it using the GODEBUG flag jstmpllitinterp=1, with the caveat that backticks will now be escaped. This should be used with caution. (CVE-2023-24538)

- The go command may generate unexpected code at build time when using cgo. This may result in unexpected behavior when running a go program which uses cgo. This may occur when running an untrusted module which contains directories with newline characters in their names. Modules which are retrieved using the go command, i.e. via go get, are not affected (modules retrieved using GOPATH-mode, i.e. GO111MODULE=off, may be affected). (CVE-2023-29402)

- On Unix platforms, the Go runtime does not behave differently when a binary is run with the setuid/setgid bits. This can be dangerous in certain cases, such as when dumping memory state, or assuming the status of standard i/o file descriptors. If a setuid/setgid binary is executed with standard I/O file descriptors closed, opening any files can result in unexpected content being read or written with elevated privileges.
Similarly, if a setuid/setgid program is terminated, either via panic or signal, it may leak the contents of its registers. (CVE-2023-29403)

- The go command may execute arbitrary code at build time when using cgo. This may occur when running go get on a malicious module, or when running any other command which builds untrusted code. This is can by triggered by linker flags, specified via a #cgo LDFLAGS directive. The arguments for a number of flags which are non-optional are incorrectly considered optional, allowing disallowed flags to be smuggled through the LDFLAGS sanitization. This affects usage of both the gc and gccgo compilers. (CVE-2023-29404)

- The go command may execute arbitrary code at build time when using cgo. This may occur when running go get on a malicious module, or when running any other command which builds untrusted code. This is can by triggered by linker flags, specified via a #cgo LDFLAGS directive. Flags containing embedded spaces are mishandled, allowing disallowed flags to be smuggled through the LDFLAGS sanitization by including them in the argument of another flag. This only affects usage of the gccgo compiler. (CVE-2023-29405)

- The HTTP/1 client does not fully validate the contents of the Host header. A maliciously crafted Host header can inject additional headers or entire requests. With fix, the HTTP/1 client now refuses to send requests containing an invalid Request.Host or Request.URL.Host value. (CVE-2023-29406)

- Extremely large RSA keys in certificate chains can cause a client/server to expend significant CPU time verifying signatures. With fix, the size of RSA keys transmitted during handshakes is restricted to <= 8192 bits. Based on a survey of publicly trusted RSA keys, there are currently only three certificates in circulation with keys larger than this, and all three appear to be test certificates that are not actively deployed. It is possible there are larger keys in use in private PKIs, but we target the web PKI, so causing breakage here in the interests of increasing the default safety of users of crypto/tls seems reasonable. (CVE-2023-29409)

- The html/template package does not properly handle HTML-like comment tokens, nor hashbang #! comment tokens, in <script> contexts. This may cause the template parser to improperly interpret the contents of <script> contexts, causing actions to be improperly escaped. This may be leveraged to perform an XSS attack. (CVE-2023-39318)

- The html/template package does not apply the proper rules for handling occurrences of <script, <!--, and </script within JS literals in <script> contexts. This may cause the template parser to improperly consider script contexts to be terminated early, causing actions to be improperly escaped. This could be leveraged to perform an XSS attack. (CVE-2023-39319)

- The go.mod toolchain directive, introduced in Go 1.21, can be leveraged to execute scripts and binaries relative to the root of the module when the go command was executed within the module. This applies to modules downloaded using the go command from the module proxy, as well as modules downloaded directly using VCS software. (CVE-2023-39320)

- Processing an incomplete post-handshake message for a QUIC connection can cause a panic. (CVE-2023-39321)

- 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. (CVE-2023-39322)

- Line directives (//line) can be used to bypass the restrictions on //go:cgo_ directives, allowing blocked linker and compiler flags to be passed during compilation. This can result in unexpected execution of arbitrary code when running go build. The line directive requires the absolute path of the file in which the directive lives, which makes exploiting this issue significantly more complex. (CVE-2023-39323)

- 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. (CVE-2023-39325)

- The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023. (CVE-2023-44487)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

All Go users should upgrade to the latest version:

# emerge --sync # emerge --ask --oneshot --verbose >=dev-lang/go-1.20.10 # emerge --ask --oneshot --verbose @golang-rebuild

Plugin Details

Severity: Critical

ID: 186294

File Name: gentoo_GLSA-202311-09.nasl

Version: 1.2

Type: local

Family: Gentoo Local Security Checks

Published: 11/27/2023

Updated: 2/9/2024

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2023-39320

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:F/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:gentoo:linux:go, cpe:/o:gentoo:linux

Required KB Items: Host/Gentoo/qpkg-list, Host/local_checks_enabled, Host/Gentoo/release

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 11/25/2023

Vulnerability Publication Date: 10/4/2022

CISA Known Exploited Vulnerability Due Dates: 10/31/2023

Reference Information

CVE: CVE-2022-2879, CVE-2022-2880, CVE-2022-41715, CVE-2022-41717, CVE-2022-41723, CVE-2022-41724, CVE-2022-41725, CVE-2023-24534, CVE-2023-24536, CVE-2023-24537, CVE-2023-24538, CVE-2023-29402, CVE-2023-29403, CVE-2023-29404, CVE-2023-29405, CVE-2023-29406, CVE-2023-29409, CVE-2023-39318, CVE-2023-39319, CVE-2023-39320, CVE-2023-39321, CVE-2023-39322, CVE-2023-39323, CVE-2023-39325, CVE-2023-44487

Detections

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