Description
The ASN.1 parser in strongSwan before 5.5.3 improperly handles CHOICE types when the x509 plugin is enabled, which allows remote attackers to cause a denial of service (infinite loop) via a crafted certificate.
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 14 | strongswan | 5.5.1-4 | — |
| Debian 13 | strongswan | 5.5.1-4 | — |
| Debian 12 | strongswan | 5.5.1-4 | — |
| Debian 8 | strongswan | 5.2.1-6+deb8u3 | DSA-3866-1 |
| Debian 7 | strongswan | 4.5.2-1.5+deb7u9 | DLA-973-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | strongswan | 5.3.5-1ubuntu3.3 | USN-3301-1 |
| Ubuntu 14.04 LTS | strongswan | 5.1.2-0ubuntu2.6 | USN-3301-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | strongswan | 5.1.3-25.1 | SUSE-SU-2017:1473-1 |
| SLES 11 SP4 | strongswan | 4.4.0-6.35.1 | SUSE-SU-2017:1471-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP2 | strongswan | 5.1.3-25.1 | SUSE-SU-2017:1473-1 |
| SLES for SAP 11 SP4 | strongswan | 4.4.0-6.35.1 | SUSE-SU-2017:1471-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | strongswan | 5.9.0-1.9 | openSUSE-SU-2024:11411-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | strongswan | 5.5.3-r0 | — |
| Alpine v3.23 | strongswan | 5.5.3-r0 | — |
| Alpine v3.22 | strongswan | 5.5.3-r0 | — |
| Alpine v3.21 | strongswan | 5.5.3-r0 | — |
| Alpine v3.20 | strongswan | 5.5.3-r0 | — |
Show 18 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | strongswan | 5.5.3-r0 | — |
| Alpine v3.18 | strongswan | 5.5.3-r0 | — |
| Alpine v3.17 | strongswan | 5.5.3-r0 | — |
| Alpine v3.16 | strongswan | 5.5.3-r0 | — |
| Alpine v3.15 | strongswan | 5.5.3-r0 | — |
| Alpine v3.14 | strongswan | 5.5.3-r0 | — |
| Alpine v3.13 | strongswan | 5.5.3-r0 | — |
| Alpine v3.12 | strongswan | 5.5.3-r0 | — |
| Alpine v3.11 | strongswan | 5.5.3-r0 | — |
| Alpine v3.10 | strongswan | 5.5.3-r0 | — |
| Alpine v3.9 | strongswan | 5.5.3-r0 | — |
| Alpine v3.8 | strongswan | 5.5.3-r0 | — |
| Alpine v3.7 | strongswan | 5.5.3-r0 | — |
| Alpine v3.6 | strongswan | 5.5.3-r0 | — |
| Alpine v3.5 | strongswan | 5.5.3-r0 | — |
| Alpine v3.4 | strongswan | 5.4.0-r2 | — |
| Alpine v3.3 | strongswan | 5.3.5-r2 | — |
| Alpine v3.2 | strongswan | 5.3.5-r2 | — |
Advisories 9
- DLA-973-1 strongswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3866-1 strongswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-3301-1 strongswan vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2017:1471-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:1473-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11411-1 strongswan-5.9.0-1.9 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- VDE-2019-009 PHOENIX CONTACT: Multiple Vulnerabilities in AXC F 2152 CERT@VDE · May 22, 2025
- WID-SEC-2024-2085 strongSwan: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Sep 9, 2024
- ICSA-19-155-01 PHOENIX CONTACT PLCNext AXC F 2152 CISA ICS & IT advisories · Jun 4, 2019
References
- 98756 vdb-entry
- https://www.strongswan.org/blog/2017/05/30/strongswan-vulnerability-%28cve-2017-9023%29.html
- DSA-3866 vendor-advisory
- USN-3301-1 vendor-advisory