Is CVE-2026-78132 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-78132 being exploited in the wild.

How severe is CVE-2026-78132?

High severity, with a CVSS score of 7.5, published 11 September 2026.

Which products and versions are affected?

strongSwan 5.1.3 through 6.0.7.

Is there a fix for CVE-2026-78132?

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-2026-78132 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-78132?

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.

CVE-2026-78132: strongSwan x509 plugin infinite loop in ietfAttrSyntax parsing

CVE-2026-78132 · Severity: high · CVSS 7.5 · Published 2026-09-11

strongSwan is an open-source VPN and IPsec implementation used to secure network communications. The x509 plugin contains an infinite loop vulnerability when parsing attribute certificates with malformed group attributes, causing the VPN service to hang and become unavailable. An attacker could exploit this by sending a specially crafted certificate during VPN authentication to trigger a denial of service.

Technologies: strongSwan. Vendors: strongSwan.

Quick answers

Is CVE-2026-78132 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-78132 being exploited in the wild.
How severe is CVE-2026-78132?: High severity, with a CVSS score of 7.5, published 11 September 2026.
Which products and versions are affected?: strongSwan 5.1.3 through 6.0.7.
Is there a fix for CVE-2026-78132?: 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-2026-78132 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-78132?: 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

The x509 plugin improperly parses the ietfAttrSyntax ASN.1 type in X.509 attribute certificates. Specifically, the SEQUENCE OF CHOICE parsing rules lack proper CHOICE flags, causing the ASN1_OPT handler to skip alternatives without consuming data when none match. This results in an infinite loop when the parser returns to the ASN1_LOOP marker. The vulnerability is triggered when a CERT payload (encoding type 10) with a malformed group attribute is received during IKEv2 handshake. Attack requires network access to the VPN endpoint and ability to send IKE messages. The fix is available in strongSwan 6.1.0 and patches are provided for older versions.

Affected products

strongSwan strongSwan 5.1.3 through 6.0.7

Timeline

2026-09-07: disclosed
2026-09-07: patched: Fixed in strongSwan 6.1.0

References

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