CVE-2026-77207
Received
Received - Intake
Null Pointer Dereference in Libreswan PKCS#7 Handling
Vulnerability report for CVE-2026-77207, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-13
Last updated on: 2026-10-13
Assigner: Libreswan Project
Description
Description
Libreswan has a null pointer dereference bug in the PKCS#7 handling code for IKE certificate authentication. When libreswan decodes an IKE CERT payload of type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with SEC_PKCS7ContainsCertsOrCrls() and then iterates the certificate list with SEC_PKCS7GetCertificateList(). The two NSS APIs disagree on a SignedData that carries a CRL but no certificates: ContainsCertsOrCrls() returns PR_TRUE (there is a CRL), so the guard passes, but GetCertificateList() returns NULL (there are no certificates). This causes libreswan to dereference a null pointer leading to a crash and restart. A malicious IKE_AUTH packet can trigger this bug, meaning the peer does not need to be authenticated. No remote code execution is possible. Continued exploitation can cause a denial of service.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| The | Libreswan | Project libreswan 4.7 |
| The | Libreswan | Project libreswan 5.4 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-252 | The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. |
| CWE-476 | The product dereferences a pointer that it expects to be valid but is NULL. |
