# CVE-2026-78130: strongSwan x509 plugin NULL pointer dereference in attribute certificate validation

Source: https://junglewise.ai/threats/cve-2026-78130-strongswan-x509-plugin-null-pointer-dereference-in-attribute  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-11. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-78130 · Severity: high · CVSS 7.5 · Published 2026-09-11

strongSwan is an open-source IPsec VPN implementation used by organizations to create secure tunnels for network traffic. The x509 plugin, which handles certificate validation, contains a flaw that crashes when processing specially crafted attribute certificates, causing denial of service and interrupting VPN connectivity.

Technologies: [strongSwan](https://junglewise.ai/threats/technologies/strongswan). Vendors: [strongSwan](https://junglewise.ai/threats/vendors/strongswan).

## Quick answers

**Is CVE-2026-78130 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-78130 being exploited in the wild.

**How severe is CVE-2026-78130?** High severity, with a CVSS score of 7.5, published 11 September 2026.

**Which products and versions are affected?** strongSwan 4.2.0 through 6.0.7.

**Is there a fix for CVE-2026-78130?** A patch was published on 2026-09-07: Fixed in strongSwan 6.1.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-78130 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-78130?** Check whether you run strongSwan at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A NULL pointer dereference exists in the x509 plugin's attribute certificate validation code. Specifically, the issued_by() and has_issuer() methods unconditionally dereference the issuerName field without checking if it is NULL; per ASN.1 specification, this field is optional in attribute certificates. An attacker with network access can craft an attribute certificate with a missing issuerName field and provide it to strongSwan for validation, triggering a crash in the acert plugin's certificate validation flow. The vulnerability requires the x509 and acert plugins to be loaded (x509 is loaded by default). Remote code execution is not possible; the impact is limited to denial of service. The fix is available in strongSwan 6.1.0 released 2026-09-07, with patches available for versions 5.1.3 and newer.

## Affected products

- strongSwan strongSwan 4.2.0 through 6.0.7

## Timeline

- 2026-09-07: disclosed
- 2026-09-07: patched: Fixed in strongSwan 6.1.0
- 2026-09-11: advisory: CVE-2026-78130 published on NVD

## References

- [https://github.com/strongswan/strongswan/releases/tag/6.1.0](https://github.com/strongswan/strongswan/releases/tag/6.1.0)
- [https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78130).html](https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78130).html)

## Related threats

- [strongSwan libcharon authentication bypass in IKEv2 CREATE_CHILD_SA handling](https://junglewise.ai/threats/cve-2026-78135-strongswan-libcharon-authentication-bypass-in-ikev2-create-child)
- [strongSwan incorrect identity binding in EAP-PEAP and EAP-TTLS](https://junglewise.ai/threats/cve-2026-78134-strongswan-incorrect-identity-binding-in-eap-peap-and-eap-ttls)
- [strongSwan libcharon use-after-free in IKEv2 rekeying collision handling](https://junglewise.ai/threats/cve-2026-78133-strongswan-libcharon-use-after-free-in-ikev2-rekeying-collision)
- [strongSwan x509 plugin infinite loop in ietfAttrSyntax parsing](https://junglewise.ai/threats/cve-2026-78132-strongswan-x509-plugin-infinite-loop-in-ietfattrsyntax-parsing)
- [strongSwan x509 plugin memory leak in attribute certificate parsing](https://junglewise.ai/threats/cve-2026-78131-strongswan-x509-plugin-memory-leak-in-attribute-certificate)