# DEBIAN-CVE-2026-21717: nodejs security update

DEBIAN-CVE-2026-21717, released March 30, 2026, fixes 1 CVE in nodejs. None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/debian-cve-2026-21717
- Platform: Linux
- Released: Mar 30, 2026
- Priority: High (Closes CVE-2026-21717, high severity)
- CVEs: 1, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://security-tracker.debian.org/tracker/CVE-2026-21717

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [nodejs](https://patchblox.com/security/data/product/linux/nodejs.md) | Debian 13.5 (trixie) | 20.19.2+dfsg-1+deb13u2 |
| [nodejs](https://patchblox.com/security/data/product/linux/nodejs.md) | Debian 14 | 22.22.2+dfsg+~cs22.19.15-1 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2026-21717](https://patchblox.com/security/data/cve/CVE-2026-21717.md) | High | A flaw in V8's string hashing mechanism causes integer-like strings to be hashed to their numeric value, making hash collisions trivially predictable. By crafting a request that causes many such collisions in V8's internal string table, an attacker can significantly degrade performance of the Node.js process.  The most common trigger is any endpoint that calls `JSON.parse()` on attacker-controlled input, as JSON parsing automatically internalizes short strings into the affected hash table.  This vulnerability affects **20.x, 22.x, 24.x, and 25.x**. | 7.5 | 0.0027 |  |

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