nsd — security advisory
When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. 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).
- Products
- nsd
- Affected versions
- Not specified
- Fixed versions
- 4.14.3-r1
- CVEs
- CVE-2026-101338
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 21:35 UTC · Revision 1
Source evidence
When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. 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).
osv:ALPINE-CVE-2026-101338
nsd
Fixed versions: 4.14.3-r1
Complete source record
{
"id": "b92cddf7ff24777aee600a137903002a923b8aa872809b9d2b0754f5ff8e8c71",
"url": "https://osv.dev/vulnerability/ALPINE-CVE-2026-101338",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "ALPINE-CVE-2026-101338",
"summary": "When a SVCB or HTTPS RR has filled the wire format RDATA up to the brim, another ECH parameter may overwrite the stack, and once beyond the limit, the base64 decoder can write attacker controlled data of unlimited size. 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).",
"evidence": "osv:ALPINE-CVE-2026-101338",
"products": [
{
"name": {
"value": "nsd",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.14.3-r1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
}
],
"severity": "high",
"structured": {
"id": "ALPINE-CVE-2026-101338",
"aliases": [
"ALPINE-CVE-2026-101338"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "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"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.14.3-r1"
}
]
}
],
"package": {
"name": "nsd",
"purl": "pkg:apk/alpine/nsd?arch=source",
"ecosystem": "Alpine:v3.24"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2026-101338.json"
},
"ecosystem_specific": {}
}
],
"modified": "2026-10-23T15:30:03.321308557Z",
"provider": "osv",
"upstream": [
"CVE-2026-101338"
],
"references": [
"https://security.alpinelinux.org/vuln/CVE-2026-101338"
]
},
"related_cves": [
{
"value": "CVE-2026-101338",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 413721,
"published_at": "2026-10-14T11:16:57.13+00:00"
}