CVE-2026-6594 | brikcss merge up to 1.3.0 __proto__/constructor.prototype/prototype prototype pollution

VDB-358229 · SUBMIT #791805 · CVE-2026-6594 BRIKCSS MERGE UP TO 1.3.0 __PROTO__/CONSTRUCTOR.PROTOTYPE/PROTOTYPE PROTOTYPE POLLUTION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.1 $0-$5k 1.86+ Summaryinfo A vulnerability marked as problematic has been reported in brikcss merge up to 1.3.0. This vulnerability affects unknown code. The manipulation of the argument __proto__/constructor.prototype/prototype leads to prototype pollution. This vulnerability is traded as CVE-2026-6594. It is possible to initiate the attack remotely. There is no exploit available. The vendor was contacted early about this disclosure but did not respond in any way. Detailsinfo A vulnerability, which was classified as critical, has been found in brikcss merge up to 1.3.0. This issue affects an unknown code. The manipulation of the argument __proto__/constructor.prototype/prototype with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. Impacted is confidentiality, integrity, and availability. The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-6594. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/19/2026). MITRE ATT&CK project uses the attack technique T1059 for this issue. The vendor was contacted early about this disclosure but did not respond in any way. There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product. Productinfo Vendor brikcss Name merge Version 1.0 1.1 1.2 1.3.0 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 7.3 VulDB Meta Temp Score: 7.1 VulDB Base Score: 7.3 VulDB Temp Score: 7.1 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Prototype pollution CWE: CWE-1321 / CWE-94 / CWE-74 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: no mitigation known Status: 🔍 0-Day Time: 🔒 Timelineinfo 04/19/2026 Advisory disclosed 04/19/2026 +0 days VulDB entry created 04/19/2026 +0 days VulDB entry last update Sourcesinfo Advisory: github.com Status: Not defined CVE: CVE-2026-6594 (🔒) GCVE (CVE): GCVE-0-2026-6594 GCVE (VulDB): GCVE-100-358229 Entryinfo Created: 04/19/2026 12:47 Changes: 04/19/2026 12:47 (52) Complete: 🔍 Submitter: sudosme Cache ID: 99:1C7:101 Submitinfo Accepted Submit #791805: brikcss @brikcss/merge 1.3.0 Prototype Pollution (by sudosme) Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸