{"id":"CVE-2026-101337","state":"PUBLISHED","title":"Stack overwrite from specially formatted base64 RDATA field","description":"When base64 data is split up in pieces, of 3 character or less, tokens were incorrectly calculated to produce 0 bytes. This enables attackers to overwrite the stack with up to 64K of attacker controlled data.  Zone files which are written out by NSD itself, such as for zones for which the NSD instance is secondary, will not be formatted like this. The zone file must be fed to NSD directly, (but it could come, for example, from an operator controlled provisioning system).","publishedAt":"2026-10-14T10:56:15.073Z","updatedAt":"2026-10-14T14:09:58.370Z","severity":{"score":8.7,"label":"High","version":"4.0","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","source":"NLnet Labs"},"assigner":"NLnet Labs","products":["NLnet Labs NSD"],"affected":[{"vendor":"NLnet Labs","product":"NSD","defaultStatus":"unaffected","versions":[{"version":"4.10.0","status":"affected","lessThan":"4.15.3","versionType":"semver"}]}],"references":["https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-101337.txt"],"weaknesses":["CWE-121"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/101xxx/CVE-2026-101337.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-101337","state":"PUBLISHED","datePublished":"2026-10-14T10:56:15.073Z","dateUpdated":"2026-10-14T14:09:58.370Z","assignerShortName":"NLnet Labs","assignerOrgId":"206fc3a0-e175-490b-9eaa-a5738056c9f6","dateReserved":"2026-09-28T14:39:03.778Z"},"containers":{"cna":{"title":"Stack overwrite from specially formatted base64 RDATA field","descriptions":[{"lang":"en","value":"When base64 data is split up in pieces, of 3 character or less, tokens were incorrectly calculated to produce 0 bytes. This enables attackers to overwrite the stack with up to 64K of attacker controlled data.  Zone files which are written out by NSD itself, such as for zones for which the NSD instance is secondary, will not be formatted like this. The zone file must be fed to NSD directly, (but it could come, for example, from an operator controlled provisioning system)."}],"affected":[{"vendor":"NLnet Labs","product":"NSD","defaultStatus":"unaffected","versions":[{"version":"4.10.0","status":"affected","lessThan":"4.15.3","versionType":"semver"}]}],"references":[{"url":"https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-101337.txt","tags":["vendor-advisory"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"When reading zone files, a resource record with a base64 RDATA field in a specially crafted presentation format, can cause an out of bounds stack overwrite which can be exploited for execution of arbitrary command."}],"cvssV4_0":{"version":"4.0","baseScore":8.7,"baseSeverity":"HIGH","vectorString":"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"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-121","lang":"en","description":"CWE-121 Stack-based Buffer Overflow","type":"CWE"}]}],"providerMetadata":{"shortName":"NLnet Labs","orgId":"206fc3a0-e175-490b-9eaa-a5738056c9f6","dateUpdated":"2026-10-14T10:56:15.073Z"},"solutions":[{"lang":"en","value":"This issue is fixed in 4.15.3 and all later versions."}],"credits":[{"lang":"en","type":"finder","value":"Qifan Zhang from Palo Alto Networks"},{"lang":"en","type":"finder","value":"Gaurang Maheta"}],"timeline":[{"time":"2026-08-13T08:12:00.000Z","lang":"en","value":"Issue reported by Qifan Zhang"},{"time":"2026-09-02T11:12:00.000Z","lang":"en","value":"Issue reported by Gaurang Maheta"},{"time":"2026-09-02T11:43:00.000Z","lang":"en","value":"NLnet Labs shares patch with Gaurang Maheta"},{"time":"2026-09-02T11:49:00.000Z","lang":"en","value":"Gaurang Maheta verifies patch"},{"time":"2026-09-27T15:03:00.000Z","lang":"en","value":"NLnet Labs shares patch with Qifan Zhang"},{"time":"2026-09-29T09:49:00.000Z","lang":"en","value":"NLnet Labs shares updated patch with Qifan Zhang"},{"time":"2026-10-02T02:03:00.000Z","lang":"en","value":"Qifan Zhang verifies patch"},{"time":"2026-10-14T12:00:00.000Z","lang":"en","value":"Fix released with version 4.15.3"}],"datePublic":"2026-10-14T12:00:00.000Z","x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-14T14:09:47.568694Z","id":"CVE-2026-101337","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-14T14:09:58.370Z"}}]}}}