CVE-2018-16151
Similar to the flaw in the same version of strongSwan regarding digestAlgorithm.parameters, 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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.89%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 after the encoded algorithm OID during PKCS#1 v1.5 signature verification. Similar to the flaw in the same version of strongSwan regarding digestAlgorithm.parameters, 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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.89% probability · 79th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- strongswan/strongswan · debian/debian linux · canonical/ubuntu linux
- Source
- cve@mitre.org
EPSS 1.9% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00077.html
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00001.html
- http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00047.html
- https://lists.debian.org/debian-lts-announce/2018/09/msg00032.htmlMailing List, Third Party Advisory
- https://security.gentoo.org/glsa/201811-16Third Party Advisory
- https://usn.ubuntu.com/3771-1/Third Party Advisory
- https://www.debian.org/security/2018/dsa-4305Third Party Advisory
- https://www.strongswan.org/blog/2018/09/24/strongswan-vulnerability-%28cve-2018-16151%2C-cve-2018-16152%29.html
- http://lists.opensuse.org/opensuse-security-announce/2019-11/msg00077.html
- http://lists.opensuse.org/opensuse-security-announce/2019-12/msg00001.html
- http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00047.html
- https://lists.debian.org/debian-lts-announce/2018/09/msg00032.htmlMailing List, Third Party Advisory
- https://security.gentoo.org/glsa/201811-16Third Party Advisory
- https://usn.ubuntu.com/3771-1/Third Party Advisory
- https://www.debian.org/security/2018/dsa-4305Third Party Advisory
- https://www.strongswan.org/blog/2018/09/24/strongswan-vulnerability-%28cve-2018-16151%2C-cve-2018-16152%29.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.