RHSA-2026:95612

The ToASCII and ToUnicode functions incorrectly accept Punycode-encoded labels that decode to an ASCII-only label.

The net/url package does not set a limit on the number of query parameters in a query.

compress provides various compression algorithms.

Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not.

Previously, DecodeElement would reset the depth counter causing it to never fire; this could lead to stack exhaustion.

When a server is configured to support unencrypted HTTP/2, it reads a few bytes from each new connection to see if they contain the HTTP/2 client preface.

Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.

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

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

Enforce a recursion limit in Unmarshal to prevent stack exhaustion when parsing deeply-nested, recursive structures.

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

When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.

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.

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.

url.Parse insufficiently validated the host/authority component and accepted some invalid URLs.

On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /.

Within HostnameError.Error(), when constructing an error string, there is no limit to the number of hosts that will be printed out.

(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries.

Previously, resolving relative paths containing parent directory ('..') segments performed string conversions and buffer rewrites on each step, resulting in quadratic time complexity and high memory allocation overhead.

Previously, pathological inputs could close an unescaped '/' early, allowing for attack-controlled data to inject arbitrary content, potentially leading to XSS.

Parsing arbitrary HTML which is then rendered using Render can result in an unexpected HTML tree.