CVE-2026-77207
Null Pointer Dereference in PKCS#7 bundle with no certificates
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.
INFO
Published Date :
Oct. 13, 2026, 10:18 p.m.
Last Modified :
Oct. 13, 2026, 10:18 p.m.
Remotely Exploit :
Yes !
Source :
d42dc95b-23f1-4e06-9076-20753a0fb0df
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | d42dc95b-23f1-4e06-9076-20753a0fb0df | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Update Libreswan to the latest version.
- Apply relevant security patches promptly.
- Monitor system stability after updates.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-77207.
| URL | Resource |
|---|---|
| https://libreswan.org/security/CVE-2026-77207/ | |
| https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-77207 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-77207
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-77207 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-77207 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by d42dc95b-23f1-4e06-9076-20753a0fb0df
Oct. 13, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-476 Added CWE CWE-252 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/77xxx/CVE-2026-77207.json">CVE-2026-77207</a> Added Reference https://libreswan.org/security/CVE-2026-77207/ Added Reference https://libreswan.org/security/CVE-2026-77207/CVE-2026-77207.txt