CVE-2021-41990

The gmp plugin in strongSwan before 5.9.4 has a remote integer overflow via a crafted certificate with an RSASSA-PSS signature. For example, this can be triggered by an unrelated self-signed CA certificate sent by an initiator. Remote code execution cannot occur.

Published: 2021-10-18 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-41990 is rated Moderate Risk (58.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.42%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-41990

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-27 1.19% 1.42% +0.23%
2 2026-05-22 1.38% 1.19% -0.19%
3 2026-04-18 — 1.38% —

Full EPSS history (41 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-41990

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2021-41990

OS Trackers for CVE-2021-41990

vendor priority summary link
alpine high CVE-2021-41990: 1 source package rows (strongswan); 29 state rows across 9 repos (3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 13, open 16. https://security.alpinelinux.org/vuln/CVE-2021-41990
debian not yet assigned CVE-2021-41990 not yet assigned priority: Debian including 1 source packages (strongswan), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-41990
redhat medium — https://access.redhat.com/security/cve/CVE-2021-41990
suse high CVE-2021-41990 severity important: SUSE including 62 source package names (strongswan, strongswan-5.8.2-11.21.1, …), 213 product×package rows across 50 product lines (HPE Helion OpenStack 8, SUSE CaaS Platform 4.0, … (50 product lines)): Fixed 136, Known Not Affected 77. https://www.suse.com/security/cve/CVE-2021-41990/
ubuntu medium CVE-2021-41990 medium priority: Ubuntu including 1 source packages (strongswan), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): released 12, not-affected 2, needs-triage 1. https://ubuntu.com/security/CVE-2021-41990

Affected software / configurations for CVE-2021-41990

Vendor Product Version Raw CPE
strongswan strongswan >= 5.6.1, < 5.9.4 cpe:2.3:a:strongswan:strongswan:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
siemens 6gk6108-4am00-2ba2_firmware — cpe:2.3:o:siemens:6gk6108-4am00-2ba2_firmware:-:*:*:*:*:*:*:*
siemens 6gk6108-4am00-2da2_firmware — cpe:2.3:o:siemens:6gk6108-4am00-2da2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5804-0ap00-2aa2_firmware — cpe:2.3:o:siemens:6gk5804-0ap00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5812-1aa00-2aa2_firmware — cpe:2.3:o:siemens:6gk5812-1aa00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5812-1ba00-2aa2_firmware — cpe:2.3:o:siemens:6gk5812-1ba00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5816-1aa00-2aa2_firmware — cpe:2.3:o:siemens:6gk5816-1aa00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5816-1ba00-2aa2_firmware — cpe:2.3:o:siemens:6gk5816-1ba00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5826-2ab00-2ab2_firmware — cpe:2.3:o:siemens:6gk5826-2ab00-2ab2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5874-2aa00-2aa2_firmware — cpe:2.3:o:siemens:6gk5874-2aa00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5874-3aa00-2aa2_firmware — cpe:2.3:o:siemens:6gk5874-3aa00-2aa2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5876-3aa02-2ba2_firmware — cpe:2.3:o:siemens:6gk5876-3aa02-2ba2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5876-3aa02-2ea2_firmware — cpe:2.3:o:siemens:6gk5876-3aa02-2ea2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5876-4aa00-2ba2_firmware — cpe:2.3:o:siemens:6gk5876-4aa00-2ba2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5876-4aa00-2da2_firmware — cpe:2.3:o:siemens:6gk5876-4aa00-2da2_firmware:-:*:*:*:*:*:*:*
siemens 6gk5856-2ea00-3da1_firmware — cpe:2.3:o:siemens:6gk5856-2ea00-3da1_firmware:-:*:*:*:*:*:*:*
siemens 6gk5856-2ea00-3aa1_firmware — cpe:2.3:o:siemens:6gk5856-2ea00-3aa1_firmware:-:*:*:*:*:*:*:*
siemens 6gk5615-0aa00-2aa2_firmware — cpe:2.3:o:siemens:6gk5615-0aa00-2aa2_firmware:-:*:*:*:*:*:*:*

References for CVE-2021-41990

cvelogic Threat Intelligence