RHSA-2026:9455

A flaw in Node.js proxy tunnel error handling could expose proxy credentials in `ERR_PROXY_TUNNEL` error messages. When proxy credentials are embedded in the proxy URL, they may be exposed through error handling paths and captured by logs, diagnostics, or other error consumers. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

A flaw in Node.js WebCrypto implementation can crash the process if the input of `subtle.encrypt()` is a multiple of 2GiB. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

A flaw in Node.js TLS hostname handling can cause Node.js unicode dot separator handling can lead to tls wildcard-depth authentication bypass due to resolver and verifier hostname normalization mismat. This can lead to confidentiality impact or bypass of the intended security boundary under affected configurations. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

The brace-expansion library generates arbitrary strings containing a common prefix and suffix. From 5.0.0 to before 5.0.6, the max option was being applied too late. When expanding a single large numeric range like {1..10000000}, the sequence generation loop generates all 10 million intermediate elements before the max limit is applied With max=10, the output is correctly limited to 10 items, but the process still allocates ~505 MB and spends ~800ms building the full intermediate array. This vulnerability is fixed in 5.0.6.

A flaw in Node.js Permission API can cause a local server to be started (via a Unix domain socket), even without the `--allow-net` permission. This vulnerability affects one supported release line: **Node.js 26**.

A flaw in Node.js TLS hostname handling can cause Embedded-nul hostnames can lead to silent authority rebinding due to c-string truncation in resolver bindings. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

A flaw in Node.js Permission API can cause a file metadata to be modified even on a path that was set as read-only with e.g. `--allow-fs-read`. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

A flaw in Node.js HTTP/2 client allows a server to send an unlimited number of ORIGIN frames, which could lead to an Out of Memory error on the client. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

A flaw in Node.js TLS host verification can cause an attacker to bypass certification validation. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.

js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.0, when merge keys are enabled, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the previous one. This issue is fixed in version 5.2.0.

js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causing O(n^2) CPU consumption when yaml.load() parses a crafted ordered-map document. This issue is fixed in version 5.2.1.

A inconsistency in Node.js hostname matching can cause a trust-policy bypass in multi-context mTLS setups. This vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.