CVE-2026-73413
Shescape: Quadratic-time denial of service in flag-protection
Description
Shescape is a simple shell escape library for JavaScript. From 2.1.11 until 2.1.14 and 3.0.1, the flag-protection loop in compose in src/internal/compose.js repeatedly joins and slices flag fragments when flagProtection is enabled, which is the default, making processing quadratic in input size across the escape, escapeAll, quote, and quoteAll APIs. An attacker who can supply a large untrusted input containing many flag fragments can consume CPU and cause denial of service. This issue is fixed in versions 2.1.14 and 3.0.1.
INFO
Published Date :
Aug. 12, 2026, 8:17 p.m.
Last Modified :
Oct. 24, 2026, 3:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Shescape to version 2.1.14 or later.
- Update Shescape to version 3.0.1 or later.
- Disable flagProtection if updating is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-73413.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-73413 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-73413
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-73413 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-73413 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 24, 2026
Action Type Old Value New Value Changed Translation Title: shescape de ericcornelissen, Description: Shescape es una simple biblioteca de escape de shell para JavaScript. Desde la versión 2.1.11 hasta la 2.1.14 y la 3.0.1, el bucle de protección de banderas en compose en src/internal/compose.js une y divide repetidamente fragmentos de banderas cuando flagProtection está habilitado, lo cual es el valor predeterminado, haciendo que el procesamiento sea cuadrático en el tamaño de la entrada a través de las APIs escape, escapeAll, quote y quoteAll. Un atacante que puede proporcionar una entrada grande no confiable que contiene muchos fragmentos de banderas puede consumir CPU y causar denegación de servicio. Este problema está solucionado en las versiones 2.1.14 y 3.0.1. Title: shescape de ericcornelissen, Description: Shescape es una simple biblioteca de escape de shell para JavaScript. Desde la versión 2.1.11 hasta la 2.1.14 y la 3.0.1, el bucle de protección de banderas en compose en src/internal/compose.js une y divide repetidamente fragmentos de banderas cuando flagProtection está habilitado, lo cual es el valor predeterminado, haciendo que el procesamiento sea cuadrático en el tamaño de la entrada a través de las APIs escape, escapeAll, quote y quoteAll. Un atacante que puede proporcionar una entrada grande no confiable que contiene muchos fragmentos de banderas puede consumir CPU y causar denegación de servicio. Este problema está solucionado en las versiones 2.1.14 y 3.0.1. -
CVE Translated by [email protected]
Oct. 23, 2026
Action Type Old Value New Value Added Translation Title: shescape de ericcornelissen, Description: Shescape es una simple biblioteca de escape de shell para JavaScript. Desde la versión 2.1.11 hasta la 2.1.14 y la 3.0.1, el bucle de protección de banderas en compose en src/internal/compose.js une y divide repetidamente fragmentos de banderas cuando flagProtection está habilitado, lo cual es el valor predeterminado, haciendo que el procesamiento sea cuadrático en el tamaño de la entrada a través de las APIs escape, escapeAll, quote y quoteAll. Un atacante que puede proporcionar una entrada grande no confiable que contiene muchos fragmentos de banderas puede consumir CPU y causar denegación de servicio. Este problema está solucionado en las versiones 2.1.14 y 3.0.1. -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 13, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-73413', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-13T14:17:17.539995Z'} -
New CVE Received by [email protected]
Aug. 12, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'ericcornelissen', 'product': 'shescape', 'versions': [{'status': 'affected', 'version': '>= 2.1.11, < 2.1.14'}, {'status': 'affected', 'version': '>= 3.0.0, < 3.0.1'}]}] Added Description Shescape is a simple shell escape library for JavaScript. From 2.1.11 until 2.1.14 and 3.0.1, the flag-protection loop in compose in src/internal/compose.js repeatedly joins and slices flag fragments when flagProtection is enabled, which is the default, making processing quadratic in input size across the escape, escapeAll, quote, and quoteAll APIs. An attacker who can supply a large untrusted input containing many flag fragments can consume CPU and cause denial of service. This issue is fixed in versions 2.1.14 and 3.0.1. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-407 Added CWE CWE-400 Added Reference https://github.com/ericcornelissen/shescape/commit/43d70b59d09bbe5c3fd02ef08b3a123e977ed9de Added Reference https://github.com/ericcornelissen/shescape/commit/b4b34c394e7f9da2775bb75381066b9a228c425f Added Reference https://github.com/ericcornelissen/shescape/pull/2649 Added Reference https://github.com/ericcornelissen/shescape/pull/2651 Added Reference https://github.com/ericcornelissen/shescape/releases/tag/v2.1.14 Added Reference https://github.com/ericcornelissen/shescape/releases/tag/v3.0.1 Added Reference https://github.com/ericcornelissen/shescape/security/advisories/GHSA-gm3r-q2wp-hw87