CVE-2026-22809 in tarteaucitron.js
Summary
by MITRE • 01/13/2026
tarteaucitron.js is a compliant and accessible cookie banner. Prior to 1.29.0, a Regular Expression Denial of Service (ReDoS) vulnerability was identified in tarteaucitron.js in the handling of the issuu_id parameter. This vulnerability is fixed in 1.29.0.
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Analysis
by VulDB Data Team • 01/14/2026
The tarteaucitron.js library serves as a cookie consent banner solution that helps websites comply with privacy regulations such as GDPR by managing user consent for cookies and tracking scripts. This JavaScript library is widely adopted across web platforms to provide accessible cookie management interfaces. The vulnerability affects versions prior to 1.29.0 where the library processes user-provided parameters through regular expression patterns without proper input validation. The specific flaw occurs during the handling of the issuu_id parameter which is used to identify and track user interactions with Issuu content within web pages.
The technical implementation of this vulnerability stems from an insufficiently crafted regular expression pattern that is susceptible to catastrophic backtracking. When maliciously crafted input is provided to the issuu_id parameter, the regular expression engine enters into a state where it performs an exponential number of operations, effectively consuming CPU resources and causing the application to become unresponsive. This behavior represents a classic Regular Expression Denial of Service (ReDoS) vulnerability classified under CWE-400, which specifically addresses improper handling of regular expressions that can lead to resource exhaustion. The vulnerability manifests when the library attempts to parse user input through a vulnerable regex pattern that fails to account for input that would trigger backtracking behavior.
The operational impact of this vulnerability extends beyond simple performance degradation to potentially enable denial of service attacks against websites utilizing the affected version of tarteaucitron.js. Attackers could exploit this weakness by crafting malicious URLs containing specially formatted issuu_id parameters that would cause the library to consume excessive processing time when attempting to validate or process these inputs. This could result in complete service unavailability for users attempting to interact with cookie consent functionality, effectively blocking access to website content until the processing completes or times out. The vulnerability is particularly concerning in high-traffic environments where multiple concurrent requests could overwhelm server resources and potentially cause cascading failures.
Mitigation strategies for this vulnerability involve upgrading to version 1.29.0 or later where the regular expression patterns have been properly reviewed and optimized to prevent catastrophic backtracking scenarios. Security teams should also implement input validation measures at the application level to sanitize any user-provided parameters before they reach the library processing layer. Additional protective measures include implementing rate limiting and request timeouts to prevent single malicious requests from consuming excessive resources. The remediation process should include comprehensive testing to ensure that the updated library functions correctly while maintaining all intended cookie consent functionality. Organizations using this library should conduct security audits to identify all instances of the vulnerable version and prioritize their remediation based on the criticality of affected systems and the potential attack surface exposure. This vulnerability aligns with ATT&CK technique T1499.004 which covers network denial of service attacks and demonstrates the importance of proper input validation in preventing resource exhaustion attacks.