High
Security advisory
programs/pluto/ikev1.c in libreswan before 3.17 retransmits in initial-responder states, which allows remote attackers to cause a denial of service (traffic amplification) via a spoofed UDP packet. NOTE: the original behavior complies with the IKEv1 protocol, but has a required security update from the libreswan vendor; as of 2016-06-10, it is expected that several other IKEv1 implementations will have vendor-required security updates, with separate CVE IDs assigned to each.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2016-5361
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 12:10 UTC · Revision 1
Source evidence
programs/pluto/ikev1.c in libreswan before 3.17 retransmits in initial-responder states, which allows remote attackers to cause a denial of service (traffic amplification) via a spoofed UDP packet. NOTE: the original behavior complies with the IKEv1 protocol, but has a required security update from the libreswan vendor; as of 2016-06-10, it is expected that several other IKEv1 implementations will have vendor-required security updates, with separate CVE IDs assigned to each.
osv:CVE-2016-5361
Complete source record
{
"id": "502fb3e896f4321c0289661096856c5011cf6edf9732d6a235a3f5fa2d746ad0",
"url": "https://osv.dev/vulnerability/CVE-2016-5361",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2016-5361",
"summary": "programs/pluto/ikev1.c in libreswan before 3.17 retransmits in initial-responder states, which allows remote attackers to cause a denial of service (traffic amplification) via a spoofed UDP packet. NOTE: the original behavior complies with the IKEv1 protocol, but has a required security update from the libreswan vendor; as of 2016-06-10, it is expected that several other IKEv1 implementations will have vendor-required security updates, with separate CVE IDs assigned to each.",
"evidence": "osv:CVE-2016-5361",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2016-5361",
"aliases": [
"CVE-2016-5361"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/libreswan/libreswan",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"last_affected": "e3ddadd311a7943bae5a844048478abedd78db6d"
},
{
"fixed": "152d6d95632d8b9477c170f1de99bcd86d7fb1d6"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:libreswan:libreswan:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"last_affected": "3.16"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "152d6d95632d8b9477c170f1de99bcd86d7fb1d6"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"versions": [
"v3.16",
"v3.16rc3",
"v3.16rc2",
"v3.14",
"v3.14rc3",
"v3.14rc2",
"v3.7",
"v3.6",
"v3.5",
"v3.4",
"v3.3",
"v3.1",
"v3.11dr1",
"v3.2rc1",
"v2.93",
"v2.92",
"libreswan-0.0.1",
"0.9.9",
"v2.6.38",
"v2.6.38rc2",
"v2.6.38rc1",
"v2.6.38dr2",
"v2.6.32",
"v2.6.37",
"v2.6.36",
"v2.6.36rc1",
"v2.6.36dr1",
"v2.6.35dr1",
"v2.6.34",
"v2.6.34rc6",
"v2.6.34rc5",
"v2.6.34rc2",
"v2.6.34rc1",
"v2.6.34dr2",
"v2.6.34dr1",
"v2.6.33rc1",
"v2.6.33dr2",
"v2.6.32rc9",
"v2.6.32rc8",
"v2.6.32rc7",
"v2.6.32rc6",
"v2.6.32rc5",
"v2.6.32rc3",
"v2.6.32rc1",
"v2.6.32dr5",
"v2.6.32dr4",
"v2.6.32dr3",
"v2.6.32dr1",
"v2.6.29rc2",
"v2.6.29",
"v2.6.28dr1",
"v2.6.27dr1",
"v2.6.26",
"v2.6.26rc1",
"v2.6.24",
"v2.6.24rc5",
"v2.6.24rc4",
"v2.6.24rc3",
"v2.6.24rc2",
"v2.6.23",
"v2.6.23dr1",
"v2.6.22dr1",
"v2.6.21",
"v2.6.20bis",
"v2.6.20rc2",
"v2.6.20",
"v2.6.19",
"v2.6.18",
"v2.6.18rc1",
"v2.6.16",
"v2.6.16dr5",
"v2.6.16dr4",
"v2.6.16dr3",
"v2.6.16dr2",
"v2.6.16dr1",
"v2.6.15",
"v2.6.15dr2",
"v2.6.14",
"v2.6.07",
"v2.6.03",
"v2.6.01",
"v2.5.03",
"v2.5.01",
"pre_FreeBSD_merge_200607"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2016-5361.json",
"vanir_signatures": [
{
"id": "CVE-2016-5361-dd7ca340",
"digest": {
"threshold": 0.9,
"line_hashes": [
"86627652806821049497760891271003665430",
"24201487968202576802260686202049093523",
"142477410369922442914278731243663070207",
"195996895018841027013861365178908799237",
"199365784008076806722690670567754263660",
"52319542269660515301921632493320412069",
"304808937194196592359069955689753404872",
"118760132748077652429291308902925545452",
"211774493758382654980443649852360948765",
"231585294691260960408558666364681762806",
"3644685348924904675938374493361824857",
"339878537889588885421261336996675171510",
"98931066176891567730705546114123706351",
"284659102604748356818408872773795585832",
"263710493929765914036940580108869563612",
"143853084601102197712553163232762326593"
]
},
"source": "https://github.com/libreswan/libreswan/commit/152d6d95632d8b9477c170f1de99bcd86d7fb1d6",
"target": {
"file": "programs/pluto/ikev1.c"
},
"deprecated": false,
"signature_type": "Line",
"signature_version": "v1"
}
],
"vanir_signatures_modified": "2026-10-20T13:15:52Z"
}
}
],
"modified": "2026-10-20T13:15:52.866966593Z",
"provider": "osv",
"references": [
"https://lists.libreswan.org/pipermail/swan-dev/2016-March/001394.html",
"https://github.com/libreswan/libreswan/commit/152d6d95632d8b9477c170f1de99bcd86d7fb1d6"
],
"provider_metadata": {}
},
"related_cves": [
{
"value": "CVE-2016-5361",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 387424,
"published_at": "2016-06-16T14:59:51.89+00:00"
}