Description
In verify_emsa_pkcs1_signature() in gmp_rsa_public_key.c in the gmp plugin in strongSwan 4.x and 5.x before 5.7.0, the RSA implementation based on GMP does not reject excess data in the digestAlgorithm.parameters field during PKCS#1 v1.5 signature verification. Consequently, a remote attacker can forge signatures when small public exponents are being used, which could lead to impersonation when only an RSA signature is used for IKEv2 authentication. This is a variant of CVE-2006-4790 and CVE-2014-1568.
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 | 5.7.0-1 | — |
| Debian 13 | strongswan | 5.7.0-1 | — |
| Debian 12 | strongswan | 5.7.0-1 | — |
| Debian 9 | strongswan | 5.5.1-4+deb9u3 | DSA-4305-1 |
| Debian 8 | strongswan | 5.2.1-6+deb8u7 | DLA-1522-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | strongswan | 5.6.2-1ubuntu2.2 | USN-3771-1 |
| Ubuntu 16.04 LTS | strongswan | 5.3.5-1ubuntu3.7 | USN-3771-1 |
| Ubuntu 14.04 LTS | strongswan | 5.1.2-0ubuntu2.10 | USN-3771-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | strongswan | 5.6.0-4.3.2 | SUSE-SU-2019:3056-1 |
| SLES 15 | strongswan | 5.6.0-4.3.2 | SUSE-SU-2019:3056-1 |
| SLES 12 SP5 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES 12 SP4 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES 12 SP3 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES 12 SP1 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES 11 SP4 | strongswan | 4.4.0-6.36.12.1 | SUSE-SU-2022:14887-1 |
| SLES for SAP 12 SP5 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES for SAP 12 SP4 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES for SAP 12 SP3 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES for SAP 12 SP2 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SLES for SAP 12 SP1 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SUSE OpenStack Cloud 8 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SUSE OpenStack Cloud 7 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | strongswan | 4.4.0-6.36.12.1 | SUSE-SU-2022:14887-1 |
| SUSE Enterprise Storage 5 | strongswan | 5.1.3-26.13.1 | SUSE-SU-2019:3266-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | strongswan | 5.6.0-lp151.4.3.1 | openSUSE-SU-2019:2598-1 |
| openSUSE Leap 15.0 | strongswan | 5.6.0-lp150.3.3.1 | openSUSE-SU-2019:2594-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | strongswan | 5.7.0-r0 | — |
| Alpine v3.23 | strongswan | 5.7.0-r0 | — |
| Alpine v3.22 | strongswan | 5.7.0-r0 | — |
| Alpine v3.21 | strongswan | 5.7.0-r0 | — |
| Alpine v3.20 | strongswan | 5.7.0-r0 | — |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | strongswan | 5.7.0-r0 | — |
| Alpine v3.18 | strongswan | 5.7.0-r0 | — |
| Alpine v3.17 | strongswan | 5.7.0-r0 | — |
| Alpine v3.16 | strongswan | 5.7.0-r0 | — |
| Alpine v3.15 | strongswan | 5.7.0-r0 | — |
| Alpine v3.14 | strongswan | 5.7.0-r0 | — |
| Alpine v3.13 | strongswan | 5.7.0-r0 | — |
| Alpine v3.12 | strongswan | 5.7.0-r0 | — |
| Alpine v3.11 | strongswan | 5.7.0-r0 | — |
| Alpine v3.10 | strongswan | 5.7.0-r0 | — |
| Alpine v3.9 | strongswan | 5.7.0-r0 | — |
| Alpine v3.8 | strongswan | 5.6.3-r2 | — |
| Alpine v3.7 | strongswan | 5.6.3-r1 | — |
| Alpine v3.6 | strongswan | 5.5.3-r2 | — |
| Alpine v3.5 | strongswan | 5.5.3-r2 | — |
Advisories 8
- DSA-4305-1 strongswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1522-1 strongswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-3771-1 strongswan vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- openSUSE-SU-2019:2598-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:14887-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3056-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2594-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:3266-1 Security update for strongswan SUSE / openSUSE Security Updates · Feb 4, 2026
References
- DSA-4305 vendor-advisory
- GLSA-201811-16 vendor-advisory
- https://www.strongswan.org/blog/2018/09/24/strongswan-vulnerability-%28cve-2018-16151%2C-cve-2018-16152%29.html
- [debian-lts-announce] 20180926 [SECURITY] [DLA 1522-1] strongswan security update mailing-list
- USN-3771-1 vendor-advisory
- openSUSE-SU-2019:2594 vendor-advisory
- openSUSE-SU-2019:2598 vendor-advisory
- openSUSE-SU-2020:0403 vendor-advisory