Vulnerability · Published Sep 3, 2026 · Assigned by GitHub_M
CVE-2026-85063node-csv: Prototype replacement still reachable via columns path
Medium 6.9
In plain English
A medium-severity prototype pollution in node-csv from adaltas. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 47% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
node-csv is a full-featured CSV parser with a simple API that is tested against large datasets. Prior to 7.0.2, csv-parse with the columns and group_columns_by_name options enabled treats a duplicate __proto__ header as an existing property in packages/csv-parse/lib/api/index.js, assigns an attacker-controlled array through obj['__proto__'], and replaces the parsed record object's prototype. A malicious CSV header can therefore inject inherited array values into the returned record, hide those inherited values from JSON serialization, and affect property enumeration and type or shape checks in applications that process the record. This issue is fixed in version 7.0.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | node-csv-parse | 6.1.0-2 | DEBIAN-CVE-2026-85063 |
| Ubuntu:26.04:LTS | node-csv-parse | no fix listed | UBUNTU-CVE-2026-85063 |
| Ubuntu:26.10 | node-csv-parse | no fix listed | UBUNTU-CVE-2026-85063 |
| npm | csv-parse | 7.0.2 | GHSA-8cw4-87c7-c6xx |
Affected products (as reported)
Weakness: CWE-1321 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/adaltas/node-csv/security/advisories/GHSA-8cw4-87c7-c6xx x_refsource_CONFIRM
- https://github.com/adaltas/node-csv/issues/496 x_refsource_MISC
- https://github.com/adaltas/node-csv/pull/497 x_refsource_MISC
- https://github.com/adaltas/node-csv/commit/eb4d1484589c976dcb977db8dd0b90e015a6f66e x_refsource_MISC