HighFix available
libwebsockets — security advisory
Stack-based Buffer Overflow in lws_adns_parse_label in warmcat libwebsockets allows, when the LWS_WITH_SYS_ASYNC_DNS flag is enabled during compilation, to overflow the label_stack, when the attacker is able to sniff a DNS request in order to craft a response with a matching id containing a label longer than the maximum.
- Products
- libwebsockets
- Affected versions
- 4.1.6-3, 4.1.6-3.1, 4.3.2-1, 4.3.2-2, 4.3.2-3, 4.3.2-4, 4.3.3-1, 4.3.3-1.1, 4.3.3-1.1~exp1, 4.3.5-1, 4.3.5-2, 4.3.5-3, 4.3.5-4, 4.3.5-4.1, 4.3.5-5, 4.3.5-6, 4.3.5-7
- Fixed versions
- 4.3.5-1+deb13u1, 4.3.5-3
- CVEs
- CVE-2025-11678
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 28 Oct 2026, 11:09 UTC · Revision 1
Source evidence
Stack-based Buffer Overflow in lws_adns_parse_label in warmcat libwebsockets allows, when the LWS_WITH_SYS_ASYNC_DNS flag is enabled during compilation, to overflow the label_stack, when the attacker is able to sniff a DNS request in order to craft a response with a matching id containing a label longer than the maximum.
osv:DEBIAN-CVE-2025-11678
libwebsockets
Fixed versions: Not specified
libwebsockets
Fixed versions: 4.3.5-1+deb13u1
libwebsockets
Fixed versions: 4.3.5-3
Complete source record
{
"id": "debf0a56164011abd4abde3e1b515236a8b95421def80fbccfa87d027c44be92",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2025-11678",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2025-11678",
"summary": "Stack-based Buffer Overflow in lws_adns_parse_label in warmcat libwebsockets allows, when the LWS_WITH_SYS_ASYNC_DNS flag is enabled during compilation, to overflow the label_stack, when the attacker is able to sniff a DNS request in order to craft a response with a matching id containing a label longer than the maximum.",
"evidence": "osv:DEBIAN-CVE-2025-11678",
"products": [
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{
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"evidence": "/affected/0/versions"
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{
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{
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{
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{
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{
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"severity": "high",
"structured": {
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"aliases": [
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"metrics": [
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"type": "CVSS_V4",
"score": "CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/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"
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"affected": [
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"package": {
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"ecosystem": "Debian:12"
},
"versions": [
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"ecosystem_specific": {
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{
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],
"package": {
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"ecosystem": "Debian:13"
},
"versions": [
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},
{
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],
"package": {
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"purl": "pkg:deb/debian/libwebsockets?arch=source&distro=forky",
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},
"ecosystem_specific": {
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}
}
],
"modified": "2026-10-09T10:00:10.721957863Z",
"provider": "osv",
"upstream": [
"CVE-2025-11678"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2025-11678"
]
},
"related_cves": [
{
"value": "CVE-2025-11678",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 111727,
"published_at": "2025-10-20T14:15:40.137+00:00"
}