SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

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…

HIGH 7.5EPSS 1.89%

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 · 78th percentile
CISA KEV
Not listed
Weakness
CWE-347
Affected
strongswan/strongswan · debian/debian linux · canonical/ubuntu linux
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.