Red Hat Security Advisory: libreswan security update
Multiple denial of service vulnerabilities and a crash issue have been identified in Libreswan, an IPsec and IKE implementation for Linux. These include DoS via RSA-SHA1 authentication payloads in IKEv1 and IKEv2, malformed fragmentation in IKEv2, and an assertion failure caused by badly formatted X.509 certificates. These flaws can cause the Libreswan daemon to crash, disrupting VPN services. Red Hat has released security updates addressing these issues for Red Hat Enterprise Linux 10 and related variants.
AI Analysis
Technical Summary
Libreswan, which provides IPsec and IKE functionality for Linux, contains several vulnerabilities that can lead to denial of service conditions. Specifically, CVE-2026-50721 and CVE-2026-50722 describe denial of service via RSA-SHA1 (PKCS#1 v1.5) authentication payloads in IKEv1 and IKEv2 respectively. CVE-2026-12413 involves denial of service through malformed fragmentation in IKEv2. Additionally, CVE-2026-14957 is an assertion failure triggered by a badly formatted X.509 certificate, causing the daemon process to crash. These vulnerabilities affect the stability and availability of the Libreswan service. Red Hat has issued an important security advisory (RHSA-2026:46398) with updated packages to remediate these issues in Red Hat Enterprise Linux 10 and its extended update support versions.
Potential Impact
Successful exploitation of these vulnerabilities results in denial of service conditions, causing the Libreswan daemon to crash or become unresponsive. This disrupts IPsec VPN tunnels and related secure communications relying on Libreswan, potentially impacting network availability and secure connectivity. There is no indication of code execution or data compromise from the provided information.
Mitigation Recommendations
Red Hat has released updated Libreswan packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 10 and its variants should apply the security update as described in Red Hat advisory RHSA-2026:46398. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying this official fix will remediate the denial of service and crash issues. No additional mitigation steps are indicated or required beyond applying the update.
Red Hat Security Advisory: libreswan security update
Description
Multiple denial of service vulnerabilities and a crash issue have been identified in Libreswan, an IPsec and IKE implementation for Linux. These include DoS via RSA-SHA1 authentication payloads in IKEv1 and IKEv2, malformed fragmentation in IKEv2, and an assertion failure caused by badly formatted X.509 certificates. These flaws can cause the Libreswan daemon to crash, disrupting VPN services. Red Hat has released security updates addressing these issues for Red Hat Enterprise Linux 10 and related variants.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Libreswan, which provides IPsec and IKE functionality for Linux, contains several vulnerabilities that can lead to denial of service conditions. Specifically, CVE-2026-50721 and CVE-2026-50722 describe denial of service via RSA-SHA1 (PKCS#1 v1.5) authentication payloads in IKEv1 and IKEv2 respectively. CVE-2026-12413 involves denial of service through malformed fragmentation in IKEv2. Additionally, CVE-2026-14957 is an assertion failure triggered by a badly formatted X.509 certificate, causing the daemon process to crash. These vulnerabilities affect the stability and availability of the Libreswan service. Red Hat has issued an important security advisory (RHSA-2026:46398) with updated packages to remediate these issues in Red Hat Enterprise Linux 10 and its extended update support versions.
Potential Impact
Successful exploitation of these vulnerabilities results in denial of service conditions, causing the Libreswan daemon to crash or become unresponsive. This disrupts IPsec VPN tunnels and related secure communications relying on Libreswan, potentially impacting network availability and secure connectivity. There is no indication of code execution or data compromise from the provided information.
Mitigation Recommendations
Red Hat has released updated Libreswan packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 10 and its variants should apply the security update as described in Red Hat advisory RHSA-2026:46398. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying this official fix will remediate the denial of service and crash issues. No additional mitigation steps are indicated or required beyond applying the update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:46398
- Cve Count
- 4
- Additional Cves
- ["CVE-2026-14957","CVE-2026-50721","CVE-2026-50722"]
- Cvss Version
- null
Threat ID: 6a885f13acd9273b493f77da
Added to database: 08/21/2026, 14:22:11 UTC
Last enriched: 08/21/2026, 14:24:26 UTC
Last updated: 08/22/2026, 03:51:58 UTC
Views: 2
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