EUVD-2026-70214

TOON: Prototype pollution when decoding untrusted TOON input...

GHSA-P95V-992W-H6C3 TOON: Prototype pollution when decoding untrusted TOON input

Summary Decoding attacker-controlled TOON containing a proto, constructor, or prototype key wrote through the object's prototype chain instead of creating an own property, polluting Object.prototype for the whole runtime. The expandPaths: 'safe' path dotted keys such as a.proto.x was the stronges...

CVE-2026-84368 joi: Prototype pollution via a `__proto__` language key in custom messages

joi is a schema description language and data validator for JavaScript. From 16.0.0 until 17.13.6 and 18.2.5, the @hapi/joi package through 17.1.1 and the successor joi package contain prototype pollution in lib/messages.js, where exports.compile and exports.merge reuse inherited objects for...

CVE-2026-84368

joi (and its predecessor @hapi/joi ), a JavaScript schema validator, is affected by a prototype pollution vulnerability in lib/messages.js. The functions exports.compile() and exports.merge() reuse inherited objects for attacker-controlled language keys (e.g., __proto__ or constructor), which can...

CVE-2026-84368 joi: Prototype pollution via a `__proto__` language key in custom messages

joi is a schema description language and data validator for JavaScript. From 16.0.0 until 17.13.6 and 18.2.5, the @hapi/joi package through 17.1.1 and the successor joi package contain prototype pollution in lib/messages.js, where exports.compile and exports.merge reuse inherited objects for...

CVE-2026-71437

Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. From version 11.5.0 until 11.16.1, Mermaid Architecture Diagrams are vulnerable to prototype pollution when a diagram defines a group with an id of proto. Because the group id is used directly ...

protobufjs: Text Format string map parsing can mutate returned map object prototype

Summary The protobuf.js text format extension parsed string-keyed map entries using ordinary property assignment. A text-format map entry with key proto could therefore change the prototype of the returned map object instead of creating an own map entry. This affected the optional Text Format...

GHSA-JFJ6-75FJ-8934 protobufjs: Text Format string map parsing can mutate returned map object prototype

Summary The protobuf.js text format extension parsed string-keyed map entries using ordinary property assignment. A text-format map entry with key proto could therefore change the prototype of the returned map object instead of creating an own map entry. This affected the optional Text Format...

CVE-2026-59876 protobufjs: Text Format string map parsing can mutate returned map object prototype

protobufjs compiles protobuf definitions into JavaScript JS functions. From 8.2.0 until 8.6.5, the protobufjs Text Format extension parsed string-keyed map entries using ordinary property assignment, allowing a map entry with key proto to change the prototype of the returned map object instead of...

parse-nested-form-data has Prototype Pollution via `__proto__` in FormData field names

Summary parseFormData walks bracket and dot-notation FormData field names into nested objects without filtering reserved property keys. A single FormData field whose name begins with proto, or contains .proto. mid-path, causes the parser to traverse onto Object.prototype and assign properties...

CVE-2026-35209 defu: Prototype pollution via `__proto__` key in defaults argument

defu is software that allows uers to assign default properties recursively. Prior to version 6.1.5, applications that pass unsanitized user input e.g. parsed JSON request bodies, database records, or config files from untrusted sources as the first argument to defu are vulnerable to prototype...

CVE-2026-35209

CVE-2026-35209 affects defu, a recursive defaults merger. Before v6.1.5, the vulnerable code path uses Object.assign({}, defaults) in _defu, which can trigger the proto setter and pollute the Object prototype, allowing attacker-controlled values to appear in the final result. The vulnerability ar...

GHSA-W48F-FWG7-WW6P @stablelib/cbor: Prototype poisoning via `__proto__` map keys in CBOR decoding

Summary @stablelib/cbor decodes CBOR maps into ordinary JavaScript objects and assigns attacker-controlled keys directly onto those objects. A CBOR map key named proto therefore changes the prototype of the decoded object instead of becoming an ordinary data property. Details The decoder builds m...

CVE-2026-33228

flatted is a circular JSON parser. Prior to version 3.4.2, the parse function in flatted can use attacker-controlled string values from the parsed JSON as direct array index keys, without validating that they are numeric. Since the internal input buffer is a JavaScript Array, accessing it with th...

CVE-2026-33228

Flatted (JSON circular parser) is affected. Prior to 3.4.2, its parse() could treat attacker-controlled string values as direct array index keys, and using the key proto on the internal Array could expose Array.prototype to the output, enabling prototype pollution. The issue has been patched in v...

GHSA-RF6F-7FWH-WJGH Prototype Pollution via parse() in NodeJS flatted

--- Summary The parse function in flatted can use attacker-controlled string values from the parsed JSON as direct array index keys, without validating that they are numeric. Since the internal input buffer is a JavaScript Array, accessing it with the key "\proto\" returns Array.prototype via the...

qs before 6.10.3, as used in Express before 4.17.3 and other products, allows attackers to cause a Node process hang for an Express application because an __ proto__ key can be used. In many typical Express use cases, an unauthenticated remote attacker can place the attack payload in the query string of the URL that is used to visit the application, such as a[__proto__]=b&a[__proto__]&a[length]=100000000. The fix was backported to qs 6.9.7, 6.8.3, 6.7.3, 6.6.1, 6.5.3, 6.4.1, 6.3.3, and 6.2.4 (and therefore Express 4.17.3, which has "deps: [email protected]" in its release description, is not vulnerable).

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