CVE-2026-39819 Invoking "go bug" follows symlinks in predictable temporary filenames in cmd/go

The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink...

CVE-2026-39825

CVE-2026-39825 concerns Go’s ReverseProxy (net/http/httputil). The issue: ReverseProxy forwards query parameters that are not visible to Rewrite/Director functions parsing parameters via url.ParseQuery. It does not respect ParseQuery’s limit on total query parameters (controlled by GODEBUG=urlmax...

CVE-2026-39819

The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink...

CVE-2026-39819 Invoking "go bug" follows symlinks in predictable temporary filenames in cmd/go

The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink...

CVE-2026-39817 Invoking "go tool pack" does not sanitize output paths in cmd/go

The "go tool pack" subcommand usually used only by the compiler as an internal tool with known-good inputs does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem...

CVE-2026-39817 Invoking "go tool pack" does not sanitize output paths in cmd/go

The "go tool pack" subcommand usually used only by the compiler as an internal tool with known-good inputs does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem...

CVE-2026-39819 Invoking "go bug" follows symlinks in predictable temporary filenames in cmd/go

The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink...

Information Exposure

Overview std/net/http/httputil is a Go standard library package std/net/http/httputil Affected versions of this package are vulnerable to Information Exposure. Go Vulnerability Report: ReverseProxy can forward queries containing parameters not visible to Rewrite functions. When used with a Rewrit...

Uncaught Exception

Overview std/net is a Go standard library package std/net Affected versions of this package are vulnerable to Uncaught Exception. Go Vulnerability Report: The Dial and LookupPort functions panic on Windows when provided with an input containing a NUL 0. Remediation Upgrade std/net to version...

GO-2026-4979 Invoking "go tool pack" does not sanitize output paths in cmd/go

The "go tool pack" subcommand usually used only by the compiler as an internal tool with known-good inputs does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem...

Cross-site Scripting (XSS)

Overview std/html/template is a Go standard library package std/html/template Affected versions of this package are vulnerable to Cross-site Scripting XSS. Go Vulnerability Report: CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a tag's attribute. If the UR...

Directory Traversal

Overview Affected versions of this package are vulnerable to Directory Traversal. Go Vulnerability Report: The "go tool pack" subcommand usually used only by the compiler as an internal tool with known-good inputs does not sanitize output filenames. Extracting a malicious archive file with the...

GO-2026-4984 Malicious module proxy can bypass checksum database in cmd/go

A malicious module proxy can exploit a flaw in the go command's validation of module checksums to bypass checksum database validation. This vulnerability affects any user using an untrusted module proxy GOMODPROXY or checksum database GOSUMDB. A malicious module proxy can serve altered versions o...

GO-2026-4982 Bypass of meta content URL escaping causes XSS in html/template

CVE-2026-27142 fixed a vulnerability in which URLs were not correctly escaped inside of a tag's attribute. If the URL content were to insert ASCII whitespaces around the '=' rune inside of the attribute, the escaper would fail to similarly escape it, leading to XSS...

Infinite loop

Overview std/net/http is a Go standard library package std/net/http Affected versions of this package are vulnerable to Infinite loop. Go Vulnerability Report: When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a...

GO-2026-4918 Infinite loop in HTTP/2 transport when given bad SETTINGS_MAX_FRAME_SIZE in net/http/internal/http2 in golang.org/x/net

When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGSMAXFRAMESIZE with a value of 0...

Symlink Attack

Overview Affected versions of this package are vulnerable to Symlink Attack. Go Vulnerability Report: The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in o...

GO-2026-4980 Escaper bypass leads to XSS in html/template

If a trusted template author were to write a tag containing an empty 'type' attribute or a 'type' attribute with an ASCII whitespace, the execution of the template would incorrectly escape any data passed into the block...

GO-2026-4978 Invoking "go bug" follows symlinks in predictable temporary filenames in cmd/go

The "go bug" command writes to two files with predictable names in the system temporary directory for example, "/tmp". An attacker with access to the temporary directory can create a symlink in one of these names, causing "go bug" to overwrite the target of the symlink...

golang: net/url: Memory exhaustion in query parameter parsing in net/url

A flaw was found in the net/url package in the Go standard library. The package does not enforce a limit on the number of unique query parameters it parses. A Go application using the net/http.Request.ParseForm method will try to process all parameters provided in the request. A specially crafted...