{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-14957",
        "assignerOrgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
        "state": "PUBLISHED",
        "assignerShortName": "libreswan",
        "dateReserved": "2026-07-07T13:39:23.932Z",
        "datePublished": "2026-09-02T02:19:00.114Z",
        "dateUpdated": "2026-09-02T02:19:00.114Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "d42dc95b-23f1-4e06-9076-20753a0fb0df",
                "shortName": "libreswan",
                "dateUpdated": "2026-09-02T02:19:00.114Z"
            },
            "title": "FIPS mode assertion failure via malicious CERT payload",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In FIPS mode, Libreswan's add_decoded_cert() function calls CERT_ExtractPublicKey() and asserts that the result is not NULL. However, CERT_ExtractPublicKey() returns NULL when public key extraction fails, for example if the RSA exponent is set to 0. A remote attacker can send a malformed X.509 certificate in a CERT payload to trigger the assertion, causing the pluto daemon to abort and restart. Continued exploitation causes a denial of service. No remote code execution is possible. Both IKEv1 and IKEv2 are affected. The vulnerability is only exploitable when both the OS and libreswan are running in FIPS mode and at least one CA certificate is loaded. The CERT payload is processed before peer authentication, so no credentials are needed to exploit this. Configurations using only PreSharedKey (PSK) authentication with no CA certificates loaded in the NSS database are not vulnerable."
                }
            ],
            "affected": [
                {
                    "vendor": "The Libreswan Project",
                    "product": "libreswan",
                    "packageName": "libreswan",
                    "collectionURL": "https://github.com/libreswan/libreswan",
                    "repo": "https://github.com/libreswan/libreswan",
                    "versions": [
                        {
                            "version": "3.0",
                            "status": "affected",
                            "lessThanOrEqual": "5.3.1",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.3.2",
                            "status": "unaffected",
                            "versionType": "semver"
                        }
                    ],
                    "defaultStatus": "unaffected",
                    "programRoutines": [
                        {
                            "name": "add_decoded_cert"
                        }
                    ]
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-617",
                            "description": "CWE-617: Reachable Assertion"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-252",
                            "description": "CWE-252: Unchecked Return Value"
                        }
                    ]
                }
            ],
            "impacts": [
                {
                    "capecId": "CAPEC-463",
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "Denial of Service via assertion failure in pluto daemon when processing a malformed X.509 certificate CERT payload in FIPS mode"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ],
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "baseScore": 7.5,
                        "baseSeverity": "HIGH",
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "scope": "UNCHANGED",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "availabilityImpact": "HIGH"
                    }
                },
                {
                    "other": {
                        "type": "vendorSeverity",
                        "content": {
                            "value": "MEDIUM",
                            "description": "Vendor-assessed severity: Medium. Exploitation requires FIPS mode to be enabled on both the OS and libreswan, and at least one CA certificate to be loaded. The daemon automatically restarts after the crash, requiring continued exploitation for sustained denial of service."
                        }
                    }
                }
            ],
            "workarounds": [
                {
                    "lang": "en",
                    "value": "No workaround is available unless one is willing to disable FIPS mode. If libreswan is only using PreSharedKey (PSK) authentication and the NSS database contains no CA certificates, CERT payloads are ignored and libreswan is not vulnerable."
                }
            ],
            "solutions": [
                {
                    "lang": "en",
                    "value": "Upgrade to libreswan 5.3.2 or later. Patches for libreswan 4.15 and 5.3 are available at https://libreswan.org/security/CVE-2026-14957/"
                }
            ],
            "exploits": [
                {
                    "lang": "en",
                    "value": "No known exploitation in the wild. Exploitation requires the target to be running in FIPS mode with at least one CA certificate loaded. The CERT payload can be sent before peer authentication, so no credentials are needed."
                }
            ],
            "configurations": [
                {
                    "lang": "en",
                    "value": "Exploitation is only possible when both the OS and libreswan are running in FIPS mode and at least one CA certificate is loaded. Both IKEv1 and IKEv2 are vulnerable. Configurations using only PreSharedKey (PSK) authentication with no CA certificates in the NSS database are not vulnerable. Use 'sudo ipsec fipsstatus' to check FIPS mode and 'sudo ipsec listcacerts' to check for loaded CA certificates."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "type": "tool",
                    "value": "Claude (Anthropic)"
                },
                {
                    "lang": "en",
                    "type": "reporter",
                    "value": "Guillaume Winter"
                }
            ],
            "source": {
                "discovery": "EXTERNAL",
                "defects": [
                    "CVE-2026-14957"
                ]
            },
            "references": [
                {
                    "name": "Libreswan Security Advisory CVE-2026-14957",
                    "url": "https://libreswan.org/security/CVE-2026-14957/CVE-2026-14957.txt",
                    "tags": [
                        "vendor-advisory"
                    ]
                },
                {
                    "name": "Libreswan CVE-2026-14957 Patches",
                    "url": "https://libreswan.org/security/CVE-2026-14957/",
                    "tags": [
                        "patch"
                    ]
                }
            ],
            "timeline": [
                {
                    "time": "2026-06-17T00:00:00.000Z",
                    "lang": "en",
                    "value": "Guillaume Winter shared a Claude audit review"
                },
                {
                    "time": "2026-07-09T00:00:00.000Z",
                    "lang": "en",
                    "value": "Advanced notice given to supported customers and distributions"
                },
                {
                    "time": "2026-07-15T00:00:00.000Z",
                    "lang": "en",
                    "value": "Public announcement and release of libreswan 5.3.2"
                }
            ],
            "taxonomyMappings": [
                {
                    "taxonomyName": "ATT&CK",
                    "taxonomyVersion": "15.1",
                    "taxonomyRelations": [
                        {
                            "taxonomyId": "T1499.004",
                            "relationshipName": "maps to",
                            "relationshipValue": "Application or System Exploitation (DoS)"
                        }
                    ]
                }
            ],
            "x_generator": {
                "engine": "cvelib 1.8.0"
            }
        }
    }
}