--- title: "CVE-2026-101337: NSD - Buffer Overflow" description: "NSD contains a buffer overflow caused by incorrect base64 token calculation when data is split into pieces of 3 characters or less, letting attackers overwrite the stack with up to 64K of controlled data, exploit requires feeding specially crafted zone files directly to NSD." url: https://panop.io/threat-heartbeat/CVE-2026-101337/ --- # CVE-2026-101337 NSD - Buffer Overflow NSD contains a buffer overflow caused by incorrect base64 token calculation when data is split into pieces of 3 characters or less, letting attackers overwrite the stack with up to 64K of controlled data, exploit requires feeding specially crafted zone files directly to NSD. CVSS base score 8.7 /10 High CISA KEV Not listed Public exploit None known Authentication Required [View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-101337) ## Details Type Buffer Overflow Impact Remote Code Execution CVSS vector CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Published 14 October 2026 Updated 15 October 2026 Weakness [CWE-121](https://cwe.mitre.org/data/definitions/121.html) ## Vendor fix Update to the latest version of NSD. Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them. ## References - [https://nvd.nist.gov/vuln/detail/CVE-2026-101337](https://nvd.nist.gov/vuln/detail/CVE-2026-101337) - [https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-101337.txt](https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-101337.txt) [← All CVEs](https://panop.io/threat-heartbeat/) ## What this record can't tell you - Whether you run the affected software, and where - Whether an attacker can actually reach and exploit it - The misconfigurations that never get a CVE number - What it would cost the business, ranked into what to fix first Panop answers these inside your environment, for this CVE and every other finding. [Book a demo](https://panop.io/demo)