# CVE-2026-77206: IKEv2 pre-authentication Null Pointer Dereference in EAP code

CVE-2026-77206 is fixed in libreswan on 1 platform, first by RHSA-2026:89748, released October 27, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-77206
- Priority: High
- CVSS: 7.5 (Important)
- EPSS: 0.0066
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 15, 2026
- Weakness: NULL Pointer Dereference
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77206

## Description

Libreswan is an implementation of IPsec and IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks such as virtual private network (VPN).    Security Fix(es):      * libreswan: IKEv2 Use-After-Free bug when using IKE-over-TCP (CVE-2026-94453)   * libreswan: IKEv2 pre-authentication Null Pointer deref in EAP code (CVE-2026-77206)   * libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS (CVE-2026-77207)   For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libreswan RHEL 8 | 0:4.12-2.el8_10.7 | [RHSA-2026:90492](https://patchblox.com/security/data/fix/linux/rhsa-2026-90492.md) | Oct 29, 2026 |
| Linux | libreswan RHEL 9 | 0:4.15-11.el9_8 | [RHSA-2026:89748](https://patchblox.com/security/data/fix/linux/rhsa-2026-89748.md) | Oct 27, 2026 |
| Linux | libreswan almalinux 8 | 4.12-2.el8_10.7 | [ALSA-2026:90492](https://patchblox.com/security/data/fix/linux/alsa-2026-90492.md) | Nov 7, 2026 |
| Linux | libreswan almalinux 9 | 4.15-11.el9_8 | [ALSA-2026:89748](https://patchblox.com/security/data/fix/linux/alsa-2026-89748.md) | Nov 7, 2026 |
| Linux | libreswan ol 8 | 0:4.12-2.0.1.el8_10.7 | [ELSA-2026-90492](https://patchblox.com/security/data/fix/linux/elsa-2026-90492.md) | Nov 7, 2026 |
| Linux | libreswan ol 9 | 0:4.15-11.0.1.el9_8 | [ELSA-2026-89748](https://patchblox.com/security/data/fix/linux/elsa-2026-89748.md) | Nov 7, 2026 |
| Linux | libreswan rocky 8 | 0:4.12-2.el8_10.7 | [RLSA-2026:90492](https://patchblox.com/security/data/fix/linux/rlsa-2026-90492.md) | Nov 7, 2026 |
| Linux | libreswan rocky 9 | 0:4.15-11.el9_8 | [RLSA-2026:89748](https://patchblox.com/security/data/fix/linux/rlsa-2026-89748.md) | Nov 7, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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