CVE-2020-1763

Name: CVE-2020-1763
Creator: NVD / NIST
Published: 2020-05-12T14:15:12.58+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 3.29%

Last modified Jun 17, 2026

CVE-2020-1763 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 3.29% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

3.29%

86.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Libreswan	Libreswan	>= 3.27, <= 3.31
Libreswan	Libreswan	3.5

References

https://bugzilla.redhat.com/show_bug.cgi?id=1813329Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1763Issue Tracking, Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdfThird Party Advisory
https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8Patch, Third Party Advisory
https://libreswan.org/security/CVE-2020-1763/CVE-2020-1763.txtPatch, Vendor Advisory
https://security.gentoo.org/glsa/202007-21Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04Third Party Advisory, US Government Resource
https://www.debian.org/security/2020/dsa-4684Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1813329Issue Tracking, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1763Issue Tracking, Third Party Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdfThird Party Advisory
https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8Patch, Third Party Advisory
https://libreswan.org/security/CVE-2020-1763/CVE-2020-1763.txtPatch, Vendor Advisory
https://security.gentoo.org/glsa/202007-21Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04Third Party Advisory, US Government Resource
https://www.debian.org/security/2020/dsa-4684Third Party Advisory

Timeline

Published: May 12, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-1763?

How severe is CVE-2020-1763?

CVE-2020-1763 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 3.29% probability of exploitation in the next 30 days.

How do I fix CVE-2020-1763?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-1763?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST