# CVE-2026-14957: FIPS mode assertion failure via malicious CERT payload

CVE-2026-14957 is fixed in 2 products on 1 platform, first by ALSA-2026:46398, released July 27, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-14957
- Priority: High
- CVSS: 7.5 (Important)
- EPSS: 0.0047
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 15, 2026
- Weakness: Reachable Assertion
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-14957

## 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):  * librenswan: IKEv1 Denial of Service via RSA-SHA1 (PKCS#1 Version 1.5 Encrypted) authentication payload (CVE-2026-50721)  * librenswan: IKEv2 Denial of Service via RSA-SHA1 (PKCS#1 RSASSA-PKCS1-v1_5) authentication payload (CVE-2026-50722)  * librenswan: IKEv2 Denial of Service via malformed fragmentation (CVE-2026-12413)  * libreswan: badly formatted X.509 certificate can cause an assertion failure that crashes the daemon process (CVE-2026-14957)  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 10 | 5.2-1.el10_0.5 | [RHSA-2026:55449](https://patchblox.com/security/data/fix/linux/rhsa-2026-55449.md) | Jul 28, 2026 |
| Linux | libreswan RHEL 8 | 0:4.12-2.el8_10.6 | [RHSA-2026:46396](https://patchblox.com/security/data/fix/linux/rhsa-2026-46396.md) | Jul 27, 2026 |
| Linux | libreswan RHEL 9 | 0:4.15-10.el9_8 | [RHSA-2026:46397](https://patchblox.com/security/data/fix/linux/rhsa-2026-46397.md) | Jul 27, 2026 |
| Linux | libreswan almalinux 10 | 5.3.2-1.el10_2 | [ALSA-2026:46398](https://patchblox.com/security/data/fix/linux/alsa-2026-46398.md) | Jul 27, 2026 |
| Linux | libreswan almalinux 8 | 4.12-2.el8_10.6 | [ALSA-2026:46396](https://patchblox.com/security/data/fix/linux/alsa-2026-46396.md) | Jul 27, 2026 |
| Linux | libreswan almalinux 9 | 4.15-10.el9_8 | [ALSA-2026:46397](https://patchblox.com/security/data/fix/linux/alsa-2026-46397.md) | Jul 27, 2026 |
| Linux | libreswan ol 10 | 0:5.3.2-1.el10_2 | [ELSA-2026-46398](https://patchblox.com/security/data/fix/linux/elsa-2026-46398.md) | Jul 27, 2026 |
| Linux | libreswan ol 8 | 0:4.12-2.0.1.el8_10.6 | [ELSA-2026-46396](https://patchblox.com/security/data/fix/linux/elsa-2026-46396.md) | Jul 27, 2026 |
| Linux | libreswan ol 9 | 0:4.15-10.0.1.el9_8 | [ELSA-2026-46397](https://patchblox.com/security/data/fix/linux/elsa-2026-46397.md) | Jul 27, 2026 |
| Linux | libreswan rocky 10 | 0:5.3.2-1.el10_2 | [RLSA-2026:46398](https://patchblox.com/security/data/fix/linux/rlsa-2026-46398.md) | Jul 28, 2026 |
| Linux | libreswan rocky 8 | 0:4.12-2.el8_10.6 | [RLSA-2026:46396](https://patchblox.com/security/data/fix/linux/rlsa-2026-46396.md) | Jul 28, 2026 |
| Linux | libreswan rocky 9 | 0:4.15-10.el9_8 | [RLSA-2026:46397](https://patchblox.com/security/data/fix/linux/rlsa-2026-46397.md) | Jul 27, 2026 |
| Linux | libreswan-minimal almalinux 10 | 5.3.2-1.el10_2 | [ALSA-2026:46398](https://patchblox.com/security/data/fix/linux/alsa-2026-46398.md) | Jul 27, 2026 |
| Linux | libreswan-minimal ol 10 | 0:5.3.2-1.el10_2 | [ELSA-2026-46398](https://patchblox.com/security/data/fix/linux/elsa-2026-46398.md) | Jul 27, 2026 |

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Data as of 2026-11-08T13:06:02Z 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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