High severity · published Sep 11, 2026
CVE-2026-78133
libcharon in strongSwan 6.0.0 through 6.0.7 has a use-after-free in IKEv2 rekeying collision handling
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
libcharon in strongSwan 6.0.0 through 6.0.7 has a use-after-free in IKEv2 rekeying collision handling.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ST
strongSwan · strongSwan
6.0.0 before 6.1.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-78133
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-78133
Patch
https://github.com/strongswan/strongswan/releases/tag/6.1.0
Mitigation
https://www.strongswan.org/blog/2026/09/07/strongswan-vulnerability-(cve-2026-78133).html
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