Focus on strongswan vulnerabilities and metrics.
Last updated: 08 Mar 2025, 23:25 UTC
This page consolidates all known Common Vulnerabilities and Exposures (CVEs) associated with strongswan. We track both calendar-based metrics (using fixed periods) and rolling metrics (using gliding windows) to give you a comprehensive view of security trends and risk evolution. Use these insights to assess risk and plan your patching strategy.
For a broader perspective on cybersecurity threats, explore the comprehensive list of CVEs by vendor and product. Stay updated on critical vulnerabilities affecting major software and hardware providers.
Total strongswan CVEs: 20
Earliest CVE date: 06 Dec 2004, 05:00 UTC
Latest CVE date: 07 Dec 2023, 05:15 UTC
Latest CVE reference: CVE-2023-41913
30-day Count (Rolling): 0
365-day Count (Rolling): 0
Calendar-based Variation
Calendar-based Variation compares a fixed calendar period (e.g., this month versus the same month last year), while Rolling Growth Rate uses a continuous window (e.g., last 30 days versus the previous 30 days) to capture trends independent of calendar boundaries.
Month Variation (Calendar): 0%
Year Variation (Calendar): -100.0%
Month Growth Rate (30-day Rolling): 0.0%
Year Growth Rate (365-day Rolling): -100.0%
Average CVSS: 4.82
Max CVSS: 10.0
Critical CVEs (≥9): 1
| Range | Count |
|---|---|
| 0.0-3.9 | 5 |
| 4.0-6.9 | 27 |
| 7.0-8.9 | 3 |
| 9.0-10.0 | 1 |
These are the five CVEs with the highest CVSS scores for strongswan, sorted by severity first and recency.
strongSwan before 5.9.12 has a buffer overflow and possible unauthenticated remote code execution via a DH public value that exceeds the internal buffer in charon-tkm's DH proxy. The earliest affected version is 5.3.0. An attack can occur via a crafted IKE_SA_INIT message.
strongSwan 5.9.8 and 5.9.9 potentially allows remote code execution because it uses a variable named "public" for two different purposes within the same function. There is initially incorrect access control, later followed by an expired pointer dereference. One attack vector is sending an untrusted client certificate during EAP-TLS. A server is affected only if it loads plugins that implement TLS-based EAP methods (EAP-TLS, EAP-TTLS, EAP-PEAP, or EAP-TNC). This is fixed in 5.9.10.
strongSwan before 5.9.8 allows remote attackers to cause a denial of service in the revocation plugin by sending a crafted end-entity (and intermediate CA) certificate that contains a CRL/OCSP URL that points to a server (under the attacker's control) that doesn't properly respond but (for example) just does nothing after the initial TCP handshake, or sends an excessive amount of application data.
In strongSwan before 5.9.5, a malicious responder can send an EAP-Success message too early without actually authenticating the client and (in the case of EAP methods with mutual authentication and EAP-only authentication for IKEv2) even without server authentication.
The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different certificates to fill the cache and later trigger the replacement of cache entries. The code attempts to select a less-often-used cache entry by means of a random number generator, but this is not done correctly. Remote code execution might be a slight possibility.
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.
The Libreswan Project has found a vulnerability in the processing of IKEv1 informational exchange packets which are encrypted and integrity protected using the established IKE SA encryption and integrity keys, but as a receiver, the integrity check value was not verified. This issue affects versions before 3.29.
The gmp plugin in strongSwan before 5.7.1 has a Buffer Overflow via a crafted certificate.
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.
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.
strongSwan 5.6.0 and older allows Remote Denial of Service because of Missing Initialization of a Variable.
In stroke_socket.c in strongSwan before 5.6.3, a missing packet length check could allow a buffer underflow, which may lead to resource exhaustion and denial of service while reading from the socket.
The rsa_pss_params_parse function in libstrongswan/credentials/keys/signature_params.c in strongSwan 5.6.1 allows remote attackers to cause a denial of service via a crafted RSASSA-PSS signature that lacks a mask generation function parameter.
strongSwan 5.2.2 and 5.3.0 allows remote attackers to cause a denial of service (daemon crash) or execute arbitrary code.
The gmp plugin in strongSwan before 5.6.0 allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted RSA signature.
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.
The gmp plugin in strongSwan before 5.5.3 does not properly validate RSA public keys before calling mpz_powm_sec, which allows remote peers to cause a denial of service (floating point exception and process crash) via a crafted certificate.
The server implementation of the EAP-MSCHAPv2 protocol in the eap-mschapv2 plugin in strongSwan 4.2.12 through 5.x before 5.3.4 does not properly validate local state, which allows remote attackers to bypass authentication via an empty Success message in response to an initial Challenge message.
strongSwan 4.3.0 through 5.x before 5.3.2 and strongSwan VPN Client before 1.4.6, when using EAP or pre-shared keys for authenticating an IKEv2 connection, does not enforce server authentication restrictions until the entire authentication process is complete, which allows remote servers to obtain credentials by using a valid certificate and then reading the responses.
strongSwan 4.5.x through 5.2.x before 5.2.1 allows remote attackers to cause a denial of service (invalid pointer dereference) via a crafted IKEv2 Key Exchange (KE) message with Diffie-Hellman (DH) group 1025.
strongSwan before 5.1.2 allows remote attackers to cause a denial of service (NULL pointer dereference and IKE daemon crash) via a crafted ID_DER_ASN1_DN ID payload.
IKEv2 in strongSwan 4.0.7 before 5.1.3 allows remote attackers to bypass authentication by rekeying an IKE_SA during (1) initiation or (2) re-authentication, which triggers the IKE_SA state to be set to established.
strongSwan 5.0.2 through 5.1.0 allows remote attackers to cause a denial of service (NULL pointer dereference and charon daemon crash) via a crafted IKEv1 fragmentation packet.
The compare_dn function in utils/identification.c in strongSwan 4.3.3 through 5.1.1 allows (1) remote attackers to cause a denial of service (out-of-bounds read, NULL pointer dereference, and daemon crash) or (2) remote authenticated users to impersonate arbitrary users and bypass access restrictions via a crafted ID_DER_ASN1_DN ID, related to an "insufficient length check" during identity comparison.
The is_asn1 function in strongSwan 4.1.11 through 5.0.4 does not properly validate the return value of the asn1_length function, which allows remote attackers to cause a denial of service (segmentation fault) via a (1) XAuth username, (2) EAP identity, or (3) PEM encoded file that starts with a 0x04, 0x30, or 0x31 character followed by an ASN.1 length value that triggers an integer overflow.
Buffer overflow in the atodn function in strongSwan 2.0.0 through 4.3.4, when Opportunistic Encryption is enabled and an RSA key is being used, allows remote attackers to cause a denial of service (pluto IKE daemon crash) and possibly execute arbitrary code via crafted DNS TXT records. NOTE: this might be the same vulnerability as CVE-2013-2053 and CVE-2013-2054.
strongSwan 4.3.5 through 5.0.3, when using the OpenSSL plugin for ECDSA signature verification, allows remote attackers to authenticate as other users via an invalid signature.
The GMP Plugin in strongSwan 4.2.0 through 4.6.3 allows remote attackers to bypass authentication via a (1) empty or (2) zeroed RSA signature, aka "RSA signature verification vulnerability."
The IKE daemon in strongSwan 4.3.x before 4.3.7 and 4.4.x before 4.4.1 does not properly check the return values of snprintf calls, which allows remote attackers to execute arbitrary code via crafted (1) certificate or (2) identity data that triggers buffer overflows.
The asn1_length function in strongSwan 2.8 before 2.8.11, 4.2 before 4.2.17, and 4.3 before 4.3.3 does not properly handle X.509 certificates with crafted Relative Distinguished Names (RDNs), which allows remote attackers to cause a denial of service (pluto IKE daemon crash) via malformed ASN.1 data. NOTE: this is due to an incomplete fix for CVE-2009-2185.
The ASN.1 parser (pluto/asn1.c, libstrongswan/asn1/asn1.c, libstrongswan/asn1/asn1_parser.c) in (a) strongSwan 2.8 before 2.8.10, 4.2 before 4.2.16, and 4.3 before 4.3.2; and (b) openSwan 2.6 before 2.6.22 and 2.4 before 2.4.15 allows remote attackers to cause a denial of service (pluto IKE daemon crash) via an X.509 certificate with (1) crafted Relative Distinguished Names (RDNs), (2) a crafted UTCTIME string, or (3) a crafted GENERALIZEDTIME string.
charon/sa/tasks/child_create.c in the charon daemon in strongSWAN before 4.3.1 switches the NULL checks for TSi and TSr payloads, which allows remote attackers to cause a denial of service via an IKE_AUTH request without a (1) TSi or (2) TSr traffic selector.
charon/sa/ike_sa.c in the charon daemon in strongSWAN before 4.3.1 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via an invalid IKE_SA_INIT request that triggers "an incomplete state," followed by a CREATE_CHILD_SA request.
The pluto IKE daemon in Openswan and Strongswan IPsec 2.6 before 2.6.21 and 2.4 before 2.4.14, and Strongswan 4.2 before 4.2.14 and 2.8 before 2.8.9, allows remote attackers to cause a denial of service (daemon crash and restart) via a crafted (1) R_U_THERE or (2) R_U_THERE_ACK Dead Peer Detection (DPD) IPsec IKE Notification message that triggers a NULL pointer dereference related to inconsistent ISAKMP state and the lack of a phase2 state association in DPD.
strongSwan 4.2.6 and earlier allows remote attackers to cause a denial of service (daemon crash) via an IKE_SA_INIT message with a large number of NULL values in a Key Exchange payload, which triggers a NULL pointer dereference for the return value of the mpz_export function in the GNU Multiprecision Library (GMP).
FreeS/WAN 1.x and 2.x, and other related products including superfreeswan 1.x, openswan 1.x before 1.0.6, openswan 2.x before 2.1.4, and strongSwan before 2.1.3, allows remote attackers to authenticate using spoofed PKCS#7 certificates in which a self-signed certificate identifies an alternate Certificate Authority (CA) and spoofed issuer and subject.