marked

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Inefficient Regular Expression Complexity in marked

### Impact _What kind of vulnerability is it?_ Denial of service. The regular expression `inline.reflinkSearch` may cause catastrophic backtracking against some strings. PoC is the following. ```javascript import * as marked from 'marked'; console.log(marked.parse(`[x]: x \\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](\\[\\](`)); ``` _Who is impacted?_ Anyone who runs untrusted markdown through marked and does not use a worker with a time limit. ### Patches _Has the problem been patched?_ Yes _What versions should users upgra…

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Marked Vulnerable to OOM Denial of Service via Infinite Recursion in marked Tokenizer

### Summary A critical Denial of Service (DoS) vulnerability exists in `[email protected]`. By providing a specific 3-byte input sequence a tab, a vertical tab, and a newline (`\x09\x0b\n`)—an unauthenticated attacker can trigger an infinite recursion loop during parsing. This leads to unbounded memory allocation, causing the host Node.js application to crash via Memory Exhaustion (OOM). ### Details The vulnerability originates in how `marked`'s block tokenizer handles unexpected whitespace characters. 1. **Tab Character (`\x09`) Consumption**: The `space()` tokenizer matches standard whitespace using the regex `/^(?:[ \t]*(?:\n|$))+/`. When parsing the malicious payload (`\x09\x0b\n`), thi…

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Regular Expression Denial of Service in marked

Versions 0.3.3 and earlier of `marked` are affected by a regular expression denial of service ( ReDoS ) vulnerability when passed inputs that reach the `em` inline rule. ## Recommendation Update to version 0.3.4 or later.

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Inefficient Regular Expression Complexity in marked

### Impact _What kind of vulnerability is it?_ Denial of service. The regular expression `block.def` may cause catastrophic backtracking against some strings. PoC is the following. ```javascript import * as marked from "marked"; marked.parse(`[x]:${' '.repeat(1500)}x ${' '.repeat(1500)} x`); ``` _Who is impacted?_ Anyone who runs untrusted markdown through marked and does not use a worker with a time limit. ### Patches _Has the problem been patched?_ Yes _What versions should users upgrade to?_ 4.0.10 ### Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ Do not run untrusted markdown through marked or run marked on a [worker](http…

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Regular Expression Denial of Service in marked

Affected versions of `marked` are vulnerable to a regular expression denial of service. The amplification in this vulnerability is significant, with 1,000 characters resulting in the event loop being blocked for around 6 seconds. ## Recommendation Update to version 0.3.9 or later.

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Regular Expression Denial of Service (REDoS) in Marked

### Impact _What kind of vulnerability is it? Who is impacted?_ [Regular expression Denial of Service](https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS) A Denial of Service attack can affect anyone who runs user generated code through `marked`. ### Patches _Has the problem been patched? What versions should users upgrade to?_ patched in v2.0.0 ### Workarounds _Is there a way for users to fix or remediate the vulnerability without upgrading?_ None. ### References _Are there any links users can visit to find out more?_ https://github.com/markedjs/marked/issues/1927 https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS…

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Marked vulnerable to XSS from data URIs

marked version 0.3.6 and earlier is vulnerable to an XSS attack in the data: URI parser.

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Multiple Content Injection Vulnerabilities in marked

Versions 0.3.0 and earlier of `marked` are affected by two cross-site scripting vulnerabilities, even when `sanitize: true` is set. The attack vectors for this vulnerability are GFM Codeblocks and JavaScript URLs. ## Recommendation Upgrade to version 0.3.1 or later.

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VBScript Content Injection in marked

Versions 0.3.2 and earlier of `marked` are affected by a cross-site scripting vulnerability even when `sanitize:true` is set. ## Proof of Concept ( IE10 Compatibility Mode Only ) `[xss link](vbscript:alert(1&#41;)` will get a link `<a href="vbscript:alert(1)">xss link</a>` ## Recommendation Update to version 0.3.3 or later.

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Marked allows Regular Expression Denial of Service (ReDoS) attacks

Marked prior to version 0.3.17 is vulnerable to a Regular Expression Denial of Service (ReDoS) attack due to catastrophic backtracking in several regular expressions used for parsing HTML tags and markdown links. An attacker can exploit this vulnerability by providing specially crafted markdown input, such as deeply nested or repetitively structured brackets or tag attributes, which cause the parser to hang and lead to a Denial of Service.

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Sanitization bypass using HTML Entities in marked

Affected versions of `marked` are susceptible to a cross-site scripting vulnerability in link components when `sanitize:true` is configured. ## Proof of Concept This flaw exists because link URIs containing HTML entities get processed in an abnormal manner. Any HTML Entities get parsed on a best-effort basis and included in the resulting link, while if that parsing fails that character is omitted. For example: A link URI such as ``` javascript&#x58document;alert&#40;1&#41; ``` Renders a valid link that when clicked will execute `alert(1)`. ## Recommendation Update to version 0.3.6 or later.

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Marked ReDoS due to email addresses being evaluated in quadratic time

Versions of `marked` from 0.3.14 until 0.6.2 are vulnerable to Regular Expression Denial of Service. Email addresses may be evaluated in quadratic time, allowing attackers to potentially crash the node process due to resource exhaustion. ## Recommendation Upgrade to version 0.6.2 or later.

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Regular Expression Denial of Service in marked

Affected versions of `marked` are vulnerable to Regular Expression Denial of Service (ReDoS). The `_label` subrule may significantly degrade parsing performance of malformed input. ## Recommendation Upgrade to version 0.7.0 or later.