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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| the libreswan Project | libreswan | from versions 3.27 till 3.31 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | libreswan | 3.32-1 | — |
| Debian 12 | libreswan | 3.32-1 | — |
| Debian 10 | libreswan | 3.27-6+deb10u1 | DSA-4684-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libreswan | No fix yet | — |
| Ubuntu 18.04 LTS | libreswan | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | libreswan | 3.29-7.el8_2 | RHSA-2020:2070 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8.1 EUS | libreswan | 3.29-7.el8_1 | RHSA-2020:2071 |
| RHEL 8.0 E4S | libreswan | 3.27-10.el8_0 | RHSA-2020:2069 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | libreswan | 3.32-r0 | — |
| Alpine v3.23 | libreswan | 3.32-r0 | — |
| Alpine v3.22 | libreswan | 3.32-r0 | — |
| Alpine v3.21 | libreswan | 3.32-r0 | — |
| Alpine v3.20 | libreswan | 3.32-r0 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | libreswan | 3.32-r0 | — |
| Alpine v3.18 | libreswan | 3.32-r0 | — |
| Alpine v3.17 | libreswan | 3.32-r0 | — |
| Alpine v3.16 | libreswan | 3.32-r0 | — |
| Alpine v3.15 | libreswan | 3.32-r0 | — |
| Alpine v3.14 | libreswan | 3.32-r0 | — |
| Alpine v3.13 | libreswan | 3.32-r0 | — |
| Alpine v3.12 | libreswan | 3.32-r0 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | libreswan | 3.29-7.0.1.el8_2 | ELSA-2020-2070 |
Advisories 6
- DSA-4684-1 libreswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RHSA-2020:2071 Red Hat Security Advisory: libreswan security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:2069 Red Hat Security Advisory: libreswan security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2020:2070 Red Hat Security Advisory: libreswan security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- ICSA-21-040-04 Siemens RUGGEDCOM ROX II CISA ICS & IT advisories · Feb 9, 2021
- ELSA-2020-2070 Important: libreswan security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 12, 2020
References
- https://libreswan.org/security/CVE-2020-1763/CVE-2020-1763.txt
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1763
- https://bugzilla.redhat.com/show_bug.cgi?id=1813329
- https://github.com/libreswan/libreswan/commit/471a3e41a449d7c753bc4edbba4239501bb62ba8
- DSA-4684 vendor-advisory
- GLSA-202007-21 vendor-advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdf
- https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04