qs's arrayLimit bypass in comma parsing allows denial of service

### Summary The `arrayLimit` option in qs does not enforce limits for comma-separated values when `comma: true` is enabled, allowing attackers to cause denial-of-service via memory exhaustion. This is a bypass of the array limit enforcement, similar to the bracket notation bypass addressed in GHSA-6rw7-vpxm-498p (CVE-2025-15284). ### Details When the `comma` option is set to `true` (not the default, but configurable in applications), qs allows parsing comma-separated strings as arrays (e.g., `?param=a,b,c` becomes `['a', 'b', 'c']`). However, the limit check for `arrayLimit` (default: 20) and the optional throwOnLimitExceeded occur after the comma-handling logic in `parseArrayValue`, enabling a bypass. This permits creation of arbitrarily large arrays from a single parameter, leading to excessive memory allocation. **Vulnerable code** (lib/parse.js: lines ~40-50): ```js if (val && typeof val === 'string' && options.comma && val.indexOf(',') > -1) {     return val.split(','); } if (options.throwOnLimitExceeded && currentArrayLength >= options.arrayLimit) {     throw new RangeError('Array limit exceeded. Only ' + options.arrayLimit + ' element' + (options.arrayLimit === 1 ? '' : 's') + ' allowed in an array.'); } return val; ``` The `split(',')` returns the array immediately, skipping the subsequent limit check. Downstream merging via `utils.combine` does not prevent allocation, even if it marks overflows for sparse arrays.This discrepancy allows attackers to send a single parameter with millions of commas (e.g., `?param=,,,,,,,,...`), allocating massive arrays in memory without triggering limits. It bypasses the intent of `arrayLimit`, which is enforced correctly for indexed (`a[0]=`) and bracket (`a[]=`) notations (the latter fixed in v6.14.1 per GHSA-6rw7-vpxm-498p). ### PoC **Test 1 - Basic bypass:** ``` npm install qs ``` ```js const qs = require('qs'); const payload = 'a=' + ','.repeat(25); // 26 elements after split (bypasses arrayLimit: 5) const options = { comma: true, arrayLimit: 5, throwOnLimitExceeded: true }; try {   const result = qs.parse(payload, options);   console.log(result.a.length); // Outputs: 26 (bypass successful) } catch (e) {   console.log('Limit enforced:', e.message); // Not thrown } ``` **Configuration:** - `comma: true` - `arrayLimit: 5` - `throwOnLimitExceeded: true` Expected: Throws "Array limit exceeded" error. Actual: Parses successfully, creating an array of length 26. ### Impact Denial of Service (DoS) via memory exhaustion.

iccDEV has Out-of-bounds Read, Heap-based Buffer Overflow and Improper Null Termination

iccDEV provides a set of libraries and tools for working with ICC color management profiles. Versions 2.3.1.1 and below are vulnerable to Out-of-bounds Read, Heap-based Buffer Overflow and Improper Null Termination through its CIccTagText::Read function. This issue is fixed in version 2.3.1.2.

@fastify/express vulnerable to Improper Handling of URL Encoding (Hex Encoding)

The @fastify/express plugin adds full Express compatibility to Fastify. A security vulnerability exists in @fastify/express prior to version 4.0.3 where middleware registered with a specific path prefix can be bypassed using URL-encoded characters (e.g., `/%61dmin` instead of `/admin`). While the middleware engine fails to match the encoded path and skips execution, the underlying Fastify router correctly decodes the path and matches the route handler, allowing attackers to access protected endpoints without the middleware constraints. The vulnerability is caused by how @fastify/express matches requests against registered middleware paths. This vulnerability is similar to, but differs from, CVE-2026-22031 because this is a different npm module with its own code. Version 4.0.3 of @fastify/express contains a patch fort the issue.

iccDEV has a heap-buffer-overflow in icXmlParseTextString()

iccDEV provides a set of libraries and tools that allow for the interaction, manipulation, and application of ICC color management profiles. Prior to version 2.3.1.2, a heap buffer over-read when the strlen() function attempts to read a non-null-terminated buffer potentially leaking heap memory contents and causing application termination. This vulnerability affects users of the iccDEV library who process ICC color profiles. ICC Profile Injection vulnerabilities arise when user-controllable input is incorporated into ICC profile data or other structured binary blobs in an unsafe manner. Version 2.3.1.2 contains a fix for the issue. No known workarounds are available.

Fastify's Content-Type header tab character allows body validation bypass

Fastify is a fast and low overhead web framework, for Node.js. Prior to version 5.7.2, a validation bypass vulnerability exists in Fastify where request body validation schemas specified by Content-Type can be completely circumvented. By appending a tab character (\t) followed by arbitrary content to the Content-Type header, attackers can bypass body validation while the server still processes the body as the original content type. This issue has been patched in version 5.7.2.

File Browser has an Authentication Bypass in User Password Update

File Browser provides a file managing interface within a specified directory and it can be used to upload, delete, preview, rename and edit files. Prior to 2.57.1, a case-sensitivity flaw in the password validation logic allows any authenticated user to change their password (or an admin to change any user's password) without providing the current password. By using Title Case field name "Password" instead of lowercase "password" in the API request, the current_password verification is completely bypassed. This enables account takeover if an attacker obtains a valid JWT token through XSS, session hijacking, or other means. This vulnerability is fixed in 2.57.1.

Improper Input Validation during User Account Creation in Splunk Enterprise

In Splunk Enterprise versions below 10.2.2, 10.0.5, 9.4.10, and 9.3.11, and Splunk Cloud Platform versions below 10.4.2603.0, 10.3.2512.6, 10.2.2510.10, 10.1.2507.20, 10.0.2503.13, and 9.3.2411.127, a user who holds a role that contains the high-privilege capability `edit_user`could create a specially crafted username that includes a null byte or a non-UTF-8 percent-encoded byte due to improper input validation.<br><br>This could lead to inconsistent conversion of usernames into a proper format for storage and account management inconsistencies, such as being unable to edit or delete affected users.

MCP Go SDK Vulnerable to Improper Handling of Case Sensitivity

The Go MCP SDK used Go's standard encoding/json.Unmarshal for JSON-RPC and MCP protocol message parsing in versions prior to 1.3.1. Go's standard library performs case-insensitive matching of JSON keys to struct field tags — a field tagged json:"method" would also match "Method", "METHOD", etc. This violated the JSON-RPC 2.0 specification, which defines exact field names. A malicious MCP peer may have been able to send protocol messages with non-standard field casing that the SDK would silently accept. This had the potential for bypassing intermediary inspection and coss-implementation inconsistency. Go's standard JSON unmarshaling was replaced with a case-sensitive decoder in commit 7b8d81c. Users are advised to update to v1.3.1 to resolve this issue.

Hono: Arbitrary file access via serveStatic vulnerability

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.12.4, when using serveStatic together with route-based middleware protections (e.g. app.use('/admin/*', ...)), inconsistent URL decoding allowed protected static resources to be accessed without authorization. The router used decodeURI, while serveStatic used decodeURIComponent. This mismatch allowed paths containing encoded slashes (%2F) to bypass middleware protections while still resolving to the intended filesystem path. This issue has been patched in version 4.12.4.

Rack: Rack::Static header_rules bypass via URL-encoded paths

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static#applicable_rules evaluates several header_rules types against the raw URL-encoded PATH_INFO, while the underlying file-serving path is decoded before the file is served. As a result, a request for a URL-encoded variant of a static path can serve the same file without the headers that header_rules were intended to apply. In deployments that rely on Rack::Static to attach security-relevant response headers to static content, this can allow an attacker to bypass those headers by requesting an encoded form of the path. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Caddy: MatchPath %xx (escaped-path) branch skips case normalization, enabling path-based route/auth bypass

Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, Caddy's HTTP `path` request matcher is intended to be case-insensitive, but when the match pattern contains percent-escape sequences (`%xx`) it compares against the request's escaped path without lowercasing. An attacker can bypass path-based routing and any access controls attached to that route by changing the casing of the request path. Version 2.11.1 contains a fix for the issue.

Traefik: lowercase `Connection` tokens can delete traefik-managed forwarded identity headers (for example, `X-Real-Ip`)

Traefik is an HTTP reverse proxy and load balancer. From version 2.11.9 to 2.11.37 and from version 3.1.3 to 3.6.8, there is a potential vulnerability in Traefik managing the Connection header with X-Forwarded headers. When Traefik processes HTTP/1.1 requests, the protection put in place to prevent the removal of Traefik-managed X-Forwarded headers (such as X-Real-Ip, X-Forwarded-Host, X-Forwarded-Port, etc.) via the Connection header does not handle case sensitivity correctly. The Connection tokens are compared case-sensitively against the protected header names, but the actual header deletion operates case-insensitively. As a result, a remote unauthenticated client can use lowercase Connection tokens (e.g. Connection: x-real-ip) to bypass the protection and trigger the removal of Traefik-managed forwarded identity headers. This issue has been patched in versions 2.11.38 and 3.6.9.

Golioth Firmware SDK < 0.22.0 Blockwise Transfer Path Out-of-Bounds Read

Golioth Firmware SDK version 0.19.1 prior to 0.22.0, fixed in commit 0e788217, contain an out-of-bounds read due to improper null termination of a blockwise transfer path. blockwise_transfer_init() accepts a path whose length equals CONFIG_GOLIOTH_COAP_MAX_PATH_LEN and copies it using strncpy() without guaranteeing a trailing NUL byte, leaving ctx->path unterminated. A later strlen() on this buffer (in golioth_coap_client_get_internal()) can read past the end of the allocation, resulting in a crash/denial of service. The input is application-controlled (not network by default).

libclamav/fsg.c in Clam AntiVirus (ClamAV) before 0.87 allows remote attackers to cause a denial of service (infinite loop) via a crafted FSG packed executable.

Apache for Apple Mac OS X 10.2.8 and 10.3.6 restricts access to files in a case sensitive manner, but the Apple HFS+ filesystem accesses files in a case insensitive manner, which allows remote attackers to read .DS_Store files and files beginning with ".ht" using alternate capitalization.

security flaw

CUPS before 1.1.21rc1 treats a Location directive in cupsd.conf as case sensitive, which allows attackers to bypass intended ACLs via a printer name containing uppercase or lowercase letters that are different from what is specified in the directive.

Apache on MacOS X Client 10.0.3 with the HFS+ file system allows remote attackers to bypass access restrictions via a URL that contains some characters whose case is not matched by Apache's filters.

Perception LiteServe 1.25 allows remote attackers to obtain source code of CGI scripts via URLs that contain MS-DOS conventions such as (1) upper case letters or (2) 8.3 file names.

Task Manager in Windows 2000 does not allow local users to end processes with uppercase letters named (1) winlogon.exe, (2) csrss.exe, (3) smss.exe and (4) services.exe via the Process tab which could allow local users to install Trojan horses that cannot be stopped with the Task Manager.

register.php in Ultimate PHP Board (UPB) 1.0 and 1.0b uses an administrative account Admin with a capital "A," but allows a remote attacker to impersonate the administrator by registering an account name of admin with a lower case "a."