Weakness (CWE)
CWE-1333: Inefficient Regular Expression Complexity
The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.
How to prevent it (4 mitigations)
-
Architecture and Design
Use regular expressions that do not support backtracking, e.g. by removing nested quantifiers.
-
System Configuration
Set backtracking limits in the configuration of the regular expression implementation, such as PHP's pcre.backtrack_limit. Also consider limits on execution time for the process.
-
Implementation
Do not use regular expressions with untrusted input. If regular expressions must be used, avoid using backtracking in the expression.
-
Implementation
Limit the length of the input that the regular expression will process.
Source: MITRE CWE-1333
256 results · Clear filters · Feed
-
Medium 5.3
nodemailer before 6.9.9 ReDoS via attachDataUrls parameter
nodemailer before 6.9.9 contains a regular expression denial of service vulnerability in email parsing when attachDataUrls parameter is set or processing embedded file attachments. Attackers can send specially crafted emails with malicious data URLs or embedd…
-
Medium 5.9
NLTK 3.10.2 Regular Expression Denial of Service via tgrep
NLTK before 3.10.3 contains a regular expression denial of service (ReDoS) vulnerability in the tgrep module. The _tgrep_node_action function compiles user-supplied regular expressions embedded in /regex/ pattern nodes and executes them via re.search against …
-
Medium 4.9
Checkmate: Regular Expression Denial of Service (ReDoS) via User-Controlled Regex in Monitor Advanced Matching
Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. From 3.5.1 until 3.9.2, an authenticated admin or superadmin can set matchMethod to …
-
Medium 5.3
n8n before 1.123.69 ReDoS via Filter and Switch Node
n8n before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1 contains a regular expression denial of service (ReDoS) vulnerability in the Filter and Switch nodes, which compile user-supplied regex patterns with new RegExp() and execute them synchronously …
-
Medium 6.0
Grav: Authenticated ReDoS via regex_replace in Twig Sandbox
Grav is a file-based Web platform. Prior to 2.0.4, Grav allowlists the regex_replace filter and function in system/config/security.yaml, and GravExtension::regexReplace() passes an editor-controlled pattern directly to preg_replace(). When security.twig_conte…
-
Medium 6.5
Wazuh 4.0.0 < 4.14.7 API DoS via Deeply Nested JSON auth_context
Wazuh 4.0.0 before 4.14.7 and 5.0.0-beta2 contain a denial of service vulnerability that allows authenticated attackers with allow_run_as enabled to exhaust CPU resources by submitting arbitrarily deeply nested JSON structures to the POST /security/user/authe…
-
Medium 5.3
vLLM: ReDoS via structured_outputs.regex in the lm-format-enforcer backend (no compile timeout) — missed sibling of CVE-2026-55574
vLLM is an inference and serving engine for large language models. Prior to 0.26.0, the structured_outputs.regex parameter in vllm/v1/structured_output/backend_lm_format_enforcer.py is passed to lmformatenforcer.RegexParser without compile_regex_with_timeout …
-
Medium 4.3
CyberChef’s pretty-recipe parser vulnerable to client-side ReDoS / CPU exhaustion when parsing a malformed #recipe= URL
CyberChef is a web app for encryption, encoding, compression, and data analysis. Prior to 11.3.0, CyberChef's pretty-recipe parser in src/core/Utils.mjs can exhaust client-side CPU when a malformed #recipe= URL fragment containing a large number of unmatched …
-
Medium 5.3
Hono: ReDoS in CORS middleware via Access-Control-Request-Headers
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.34, the built-in CORS middleware, hono/cors, is vulnerable to a regular expression denial of service (ReDoS). During a preflight OPTIONS request, the middlewar…
-
Medium 5.3
SvelteKit: ReDoS (O(n^2)) in content negotiation — unauthenticated DoS via the Accept header
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. Prior to 2.70.2, the content negotiation header parser used by SvelteKit's request handling (for headers such as Accept) uses a regular expression vulnerable to …
-
Medium 6.5
Open WebUI: Any authenticated user can stall a worker via a knowledge-search pattern that backtracks catastrophically
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 until 0.11.0, the built-in knowledge search path in backend/open_webui/tools/knowledge_fs.py and backend/open_webui/tools/builtin.py let a chat participant choose…
-
Medium 6.5
Open WebUI: Instance-wide stall via automation recurrence rules that force multi-second parsing
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.0, automation recurrence parsing in backend/open_webui/utils/automations.py anchored minutely and hourly rules at a fixed date of 2000-01-01 and then w…
-
Medium 5.3
Apache Superset: Regular Expression Denial of Service (ReDoS) in SQL Parser
A Regular Expression Denial of Service (ReDoS) vulnerability exists in Apache Superset versions 1.5.0 through 5.0.0. The vulnerability is located in the sql_parse.py component, specifically within the SQL_REGEX used for parsing SQL statements in the sqlparse …
-
Medium 6.9
ReDoS in Open Mercato
Open Mercato does not validate regex rules. An attacker with privileges to create the regex rule can add an unsafe regex to a field. When someone provide the proper string it can result in a DoS attack. This issue was fixed in version 0.6.4.
-
Medium 6.5
Grav < 2.0.4 ReDoS via regex_replace in Sandbox
Grav before 2.0.4 contains a regular expression denial of service (ReDoS) vulnerability in the regex_replace filter and function, which are allowlisted in the Twig content sandbox. When Twig processing in page content is enabled (security.twig_content.process…
-
Medium 5.3
UAParser.js: Unbounded `Sec-CH-UA-Model` parsing can trigger ReDoS in `withClientHints()`
UAParser.js is a JavaScript library to detect browsers, operating systems, CPUs, and devices from user-agent data. From 2.0.1 until 2.0.10, a regular expression denial-of-service vulnerability exists when using the Client Hints API. By sending a crafted Sec-C…
-
Medium 6.5
Crafted message attachment causes client-side denial of service via markdown parser regex backtracking in Mattermost
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticated attacker to cause a denial of service for all users in a channel via a post c…
-
Medium 6.5
Open WebUI: ReDoS in skill-mention regexes causes whole-instance DoS on default config
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.2 before 0.10.0, the SKILL_MENTION_RE and strip_re regular expressions in backend/open_webui/utils/middleware.py parsed <$skillId|label> skill mentions with overlap…
-
Medium 6.5
Guardrails-detectors: guardrails-detectors: unauthenticated regular-expression denial of service (redos) via detector_params.regex
A flaw was found in `guardrails-detectors`, a component of Red Hat OpenShift AI. This vulnerability, known as Regular Expression Denial of Service (ReDoS), allows a remote attacker to provide specially crafted regular expressions to the public detection API. …
-
Medium —
@asymmetric-effort/nogginlessdom vulnerable to ReDoS via user-controlled regex in HTMLInputElement pattern validation
## Summary The `HTMLInputElement.checkValidity()` method constructed a `RegExp` directly from the user-controlled `pattern` property without any sanitization or timeout protection. This allowed an attacker to inject a regex with catastrophic backtracking, fre…
-
Medium 6.5
LobeChat < 2.2.10-canary.15 - Regular Expression Denial of Service in GitHub Skill Import
LobeChat before version 2.2.10-canary.15 contains a regular expression denial of service (ReDoS) vulnerability that allows authenticated attackers to block the Node.js event loop by supplying a catastrophic-backtracking pattern in a GitHub repository URL path…
-
Medium 4.3
vllm - Regular Expression Denial of Service in Multiple Components
vLLM versions >= 0.6.3 and < 0.9.0 contain multiple regular expression denial of service (ReDoS) vulnerabilities. Several regex patterns — in vllm/lora/utils.py, the phi4mini tool parser, and the OpenAI-compatible serving chat endpoint — are susceptible to ca…
-
Medium 4.3
Bleach linkify(parse_email=True) CPU exhaustion via unbounded email regex scanning
## Summary Bleach 6.3.0 exposes a documented email-linkification path through `bleach.linkify(..., parse_email=True)`. The implementation scans attacker-controlled text with `EMAIL_RE.finditer()` over the full character token and has no length, timeout, or li…
-
Medium 5.9
Svelte: ReDoS in `<svelte:element>` Tag Validation
Svelte is a performance oriented web framework. From version 5.51.5 to before version 5.55.7, an internal regex in the Svelte runtime can take exponential time to test in <svelte:element this={tag}></svelte:element>. This issue has been patched in version 5.5…
-
Medium 6.9
Internationalized Domain Names in Applications (IDNA): Specially crafted inputs to idna.encode() can bypass CVE-2024-3651 fix
Internationalized Domain Names in Applications (IDNA) for Python provides support for Internationalized Domain Names in Applications (IDNA) and Unicode IDNA Compatibility Processing. In versions prior to 3.15, payloads such as `"\u0660" * N` or `"\u30fb" * N …
-
Medium 4.3
johnhuang316 code-index-mcp search_code_advanced is_safe_regex_pattern redos
A weakness has been identified in johnhuang316 code-index-mcp up to 2.14.0. Affected is the function is_safe_regex_pattern of the component search_code_advanced. Executing a manipulation of the argument regex can lead to inefficient regular expression complex…
-
Medium 4.3
wonderwhy-er DesktopCommanderMCP start_search search-manager.ts redos
A security flaw has been discovered in wonderwhy-er DesktopCommanderMCP up to 0.2.38. This impacts an unknown function of the file src/search-manager.ts of the component start_search. Performing a manipulation of the argument SearchResult[] results in ineffic…
-
Medium 4.3
Enderfga claw-orchestrator Session Grep Endpoint embedded-server.ts validateRegex redos
A security vulnerability has been detected in Enderfga claw-orchestrator up to 3.7.0. The impacted element is the function validateRegex of the file claw-orchestrator/src/embedded-server.ts of the component Session Grep Endpoint. The manipulation of the argum…
-
Medium 6.5
Nautobot: Object bulk rename UI actions vulnerable to denial of service by crafted regular expression (REDoS)
Nautobot is a Network Source of Truth and Network Automation Platform. Prior to 2.4.33 and 3.1.2, Nautobot UI object-bulk-rename endpoints (for example, /dcim/interfaces/rename/) were vulnerable to application-wide denial of service via maliciously crafted re…
-
Medium 5.4
ShellHub: Crash-DoS via field injection in filter and sort-by parameters
ShellHub is a centralized SSH gateway. Prior to 0.24.2, the device list endpoint accepts user-controlled identifiers in the the name field of each filter property in the base64-encoded filter query parameter and the sort_by query parameter, which are then pas…
-
Medium 5.3
Zod jsVideoUrlParser util.js getTime redos
A weakness has been identified in Zod jsVideoUrlParser up to 0.5.1. The impacted element is the function getTime in the library lib/util.js. This manipulation of the argument timestamp causes inefficient regular expression complexity. It is possible to initia…
-
Medium 4.2
ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification
fast-jwt provides fast JSON Web Token (JWT) implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled an…
-
Medium —
skilleton has improper input handling in repository/path processing
## Summary `skilleton` versions prior to `0.3.1` include security-related weaknesses in repository normalization and path handling logic. Version `0.3.1` contains fixes and additional test coverage for these issues. ## Affected Versions `<0.3.1` ## Patched Ve…
-
Medium 6.5
PraisonAI: ReDoS via Unvalidated User-Controlled Regex in MCPToolIndex.search_tools()
PraisonAI is a multi-agent teams system. Prior to version 4.5.90, MCPToolIndex.search_tools() compiles a caller-supplied string directly as a Python regular expression with no validation, sanitization, or timeout. A crafted regex causes catastrophic backtrack…
-
Medium 5.9
path-to-regexp vulnerable to Regular Expression Denial of Service via multiple wildcards
Impact: When using multiple wildcards, combined with at least one parameter, a regular expression can be generated that is vulnerable to ReDoS. This backtracking vulnerability requires the second wildcard to be somewhere other than the end of the path. Unsafe…
-
Medium 6.9
Rails Active Support has a possible ReDoS vulnerability in number_to_delimited
Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. `NumberToDelimitedConverter` uses a lookahead-based regular expression with `gsub!` to insert thousands delimiters. Prior to versions 8.1.2.1, 8.0.4.…
-
Medium 6.5
OpenClaw < 2026.2.19 - ReDoS and Regex Injection via Unescaped Feishu Mention Metadata
OpenClaw versions prior to 2026.2.19 construct RegExp objects directly from unescaped Feishu mention metadata in the stripBotMention function, allowing regex injection and denial of service. Attackers can craft nested-quantifier patterns or metacharacters in …
-
Medium 5.9
cpp-httplib: Stack Overflow Denial of Service (DoS) via std::regex in multipart filename parsing
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.37.0, cpp-httplib uses std::regex (libstdc++) to parse RFC 5987 encoded filename* values in multipart Content-Disposition headers. The regex engine in libstdc…
-
Medium 4.9
Inefficient Regular Expression Complexity in Kibana Leading to Denial of Service
Inefficient Regular Expression Complexity (CWE-1333) in the AI Inference Anonymization Engine in Kibana can lead Denial of Service via Regular Expression Exponential Blowup (CAPEC-492).
-
Medium 5.3
markdown-it is has a Regular Expression Denial of Service (ReDoS)
Versions of the package markdown-it from 13.0.0 and before 14.1.1 are vulnerable to Regular Expression Denial of Service (ReDoS) due to the use of the regex /\*+$/ in the linkify function. An attacker can supply a long sequence of * characters followed by a n…