CVE-2026-13311: CWE-407 Inefficient Algorithmic Complexity in ljharb shell-quote
shell-quote prior to 1.8.5 finalizes parsed tokens in parse() using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on every iteration. As a result parse() runs in O(n^2) time relative to the number of input tokens. An attacker who can supply an attacker-controlled string to any code path that calls parse() (no shell metacharacters are required; plain space-separated words suffice) can block the single-threaded Node.js event loop for an extended period with a small input, resulting in a denial of service. There is no code execution or data disclosure; impact is to availability only. Fixed in 1.8.5.
AI Analysis
Technical Summary
The ljharb shell-quote library versions up to 1.8.4 contain an inefficient algorithmic complexity issue (CWE-407) in the parse() function. The function finalizes parsed tokens using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on each iteration, resulting in O(n^2) time complexity relative to input size. An attacker supplying a crafted string with space-separated tokens can cause the single-threaded Node.js event loop to be blocked for an extended period, causing a denial of service. No shell metacharacters are required for exploitation. The vulnerability impacts availability only and is fixed in version 1.8.5.
Potential Impact
This vulnerability allows an attacker to cause a denial of service by blocking the Node.js event loop with a crafted input string, impacting application availability. There is no risk of code execution or data disclosure. The severity is high due to the potential for service disruption.
Mitigation Recommendations
A fix is available in ljharb shell-quote version 1.8.5. Users should upgrade to version 1.8.5 or later to remediate this vulnerability. No other mitigation is indicated.
CVE-2026-13311: CWE-407 Inefficient Algorithmic Complexity in ljharb shell-quote
Description
shell-quote prior to 1.8.5 finalizes parsed tokens in parse() using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on every iteration. As a result parse() runs in O(n^2) time relative to the number of input tokens. An attacker who can supply an attacker-controlled string to any code path that calls parse() (no shell metacharacters are required; plain space-separated words suffice) can block the single-threaded Node.js event loop for an extended period with a small input, resulting in a denial of service. There is no code execution or data disclosure; impact is to availability only. Fixed in 1.8.5.
CVSS v4.0
Score 8.7high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The ljharb shell-quote library versions up to 1.8.4 contain an inefficient algorithmic complexity issue (CWE-407) in the parse() function. The function finalizes parsed tokens using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on each iteration, resulting in O(n^2) time complexity relative to input size. An attacker supplying a crafted string with space-separated tokens can cause the single-threaded Node.js event loop to be blocked for an extended period, causing a denial of service. No shell metacharacters are required for exploitation. The vulnerability impacts availability only and is fixed in version 1.8.5.
Potential Impact
This vulnerability allows an attacker to cause a denial of service by blocking the Node.js event loop with a crafted input string, impacting application availability. There is no risk of code execution or data disclosure. The severity is high due to the potential for service disruption.
Mitigation Recommendations
A fix is available in ljharb shell-quote version 1.8.5. Users should upgrade to version 1.8.5 or later to remediate this vulnerability. No other mitigation is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- harborist
- Date Reserved
- 2026-06-25T04:39:03.579Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3cbd214853345fc16627b6
Added to database: 06/25/2026, 05:31:13 UTC
Last enriched: 06/25/2026, 05:45:52 UTC
Last updated: 08/08/2026, 00:41:11 UTC
Views: 179
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