CVE catalog

CVE-2020-1763

libreswan affected and fixed versions

An out-of-bounds buffer read flaw was found in the pluto daemon of libreswan from versions 3.27 till 3.31 where, an unauthenticated attacker could use this flaw to crash libreswan by sending specially-crafted IKEv1 Informational Exchange packets. The daemon respawns after the crash.

Severity: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: May 11, 2020, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 3.57% · Oct 27, 2026

Projects and upstream resources

[libreswan][Source-reported homepage]

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Distribution / release	Package	Version	Status	Source
Debiantrixie	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debiantrixie	libreswan	`5.2-2.2`	Fixed	[CVE-2020-1763]
Debiansid	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debiansid	libreswan	`5.2-2.5`	Fixed	[CVE-2020-1763]
Debianforky	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debianforky	libreswan	`5.2-2.5`	Fixed	[CVE-2020-1763]
Debianbookworm	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debianbookworm	libreswan	`4.10-2+deb12u1`	Fixed	[CVE-2020-1763]

Showing 8 fix observations. All 19 observations, including unknown and conflicting reports, are available below.

Provider details and historical evidence

Distribution / release	Package	Version	Status	Source
UnknownRelease not reported	libreswan	`3.32-1`	UnknownSource applicability is not established	Provider not reported
Debianbookworm	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debianbookworm	libreswan	`4.10-2+deb12u1`	Fixed	[CVE-2020-1763]
Debianforky	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debianforky	libreswan	`5.2-2.5`	Fixed	[CVE-2020-1763]
Debiansid	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debiansid	libreswan	`5.2-2.5`	Fixed	[CVE-2020-1763]
Debiantrixie	libreswan	`3.32-1`	FixedDistribution-reported fixed boundary	[CVE-2020-1763]
Debiantrixie	libreswan	`5.2-2.2`	Fixed	[CVE-2020-1763]
Ubuntu18.04	libreswan	`3.20-7build1`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.21-2`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.22-1`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.22-2`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.22-3`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.22-4`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.23-1`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu18.04	libreswan	`3.23-4`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu20.04	libreswan	`3.29-2`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC
Ubuntu20.04	libreswan	`3.29-2build1`	UnknownSource applicability is not established	[UBUNTU-CVE-2020-1763]Oct 24, 2025, 4:48:15 AM UTC

Original provider fields

{
  "package_releases": [
    {
      "name": "libreswan",
      "status": "fixed",
      "release": "sid",
      "version": "5.2-2.5"
    },
    {
      "name": "libreswan",
      "status": "fixed",
      "release": "forky",
      "version": "5.2-2.5"
    },
    {
      "name": "libreswan",
      "status": "fixed",
      "release": "trixie",
      "version": "5.2-2.2"
    },
    {
      "name": "libreswan",
      "status": "fixed",
      "release": "bookworm",
      "version": "4.10-2+deb12u1"
    }
  ],
  "fixed_versions": [
    {
      "bug": 960458,
      "name": "libreswan",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": "3.32-1"
    },
    {
      "bug": 960458,
      "name": "libreswan",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": "3.32-1"
    },
    {
      "bug": 960458,
      "name": "libreswan",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": "3.32-1"
    },
    {
      "bug": 960458,
      "name": "libreswan",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": "3.32-1"
    }
  ],
  "distribution_packages": [
    {
      "name": "libreswan",
      "fixed_version": "3.32-1",
      "applicability_unknown": true
    },
    {
      "name": "libreswan",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "18.04",
      "versions": [
        "3.20-7build1",
        "3.21-2",
        "3.22-1",
        "3.22-2",
        "3.22-3",
        "3.22-4",
        "3.23-1",
        "3.23-4"
      ],
      "ecosystem": "deb",
      "provider_url": "https://osv.dev/vulnerability/UBUNTU-CVE-2020-1763",
      "fixed_version": "",
      "provider_source": "pypi",
      "provider_record_id": "UBUNTU-CVE-2020-1763",
      "provider_updated_at": "2025-10-24T04:48:15Z",
      "applicability_unknown": true
    },
    {
      "name": "libreswan",
      "distro": "ubuntu",
      "ranges": [
        {
          "type": "ECOSYSTEM",
          "events": [
            {
              "introduced": "0"
            }
          ]
        }
      ],
      "release": "20.04",
      "versions": [
        "3.29-2",
        "3.29-2build1"
      ],
      "ecosystem": "deb",
      "provider_url": "https://osv.dev/vulnerability/UBUNTU-CVE-2020-1763",
      "fixed_version": "",
      "provider_source": "pypi",
      "provider_record_id": "UBUNTU-CVE-2020-1763",
      "provider_updated_at": "2025-10-24T04:48:15Z",
      "applicability_unknown": true
    }
  ]
}

[Debian bug #960458]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[libreswan]Unknown
Details (2)
- 4.10-2+deb12u1 · amd64 · bookworm
  Fixed · Fixed: 3.32-1
  dsa · libreswan · debian · bookworm; dsa · libreswan · debian · 12
- 4.10-2+deb12u1 · arm64 · bookworm
  Fixed · Fixed: 3.32-1
  dsa · libreswan · debian · bookworm; dsa · libreswan · debian · 12

[Debian 13 (Trixie)]

[libreswan]Unknown
Details (2)
- 5.2-2.2 · amd64 · trixie
  Fixed · Fixed: 3.32-1
  dsa · libreswan · debian · 13
- 5.2-2.2 · arm64 · trixie
  Fixed · Fixed: 3.32-1
  dsa · libreswan · debian · 13

Observed: Oct 23, 2026, 5:48:53 PM UTC

References

[CISA cybersecurity advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]