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 assertion failure from badly formatted X.509 certificates causing daemon crashes. Red Hat has issued an important security advisory with updates for Red Hat Enterprise Linux 10.0 Extended Update Support to address these issues.
AI Analysis
Technical Summary
Libreswan, a Linux implementation of IPsec and IKE protocols, contains several vulnerabilities that can lead to denial of service conditions. CVE-2026-50721 and CVE-2026-50722 describe DoS attacks via RSA-SHA1 authentication payloads in IKEv1 and IKEv2 respectively. CVE-2026-12413 involves a DoS caused by malformed fragmentation in IKEv2. CVE-2026-14957 is an assertion failure triggered by a badly formatted X.509 certificate, crashing the libreswan daemon. These vulnerabilities affect Red Hat Enterprise Linux 10.0 Extended Update Support and related variants. Red Hat has released security updates to remediate these issues as detailed in advisory RHSA-2026:55449.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service by crashing the libreswan daemon or disrupting IPsec VPN tunnels. This impacts the availability of secure network communications relying on libreswan. There is no indication of remote code execution or data compromise. No known exploits in the wild have been reported.
Mitigation Recommendations
Red Hat has released security updates for libreswan in Red Hat Enterprise Linux 10.0 Extended Update Support to fix these vulnerabilities. Users should apply the update as described in Red Hat advisory RHSA-2026:55449. Patch status is confirmed by the vendor advisory. No additional mitigation steps are specified or required beyond applying the official 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 assertion failure from badly formatted X.509 certificates causing daemon crashes. Red Hat has issued an important security advisory with updates for Red Hat Enterprise Linux 10.0 Extended Update Support to address these issues.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Libreswan, a Linux implementation of IPsec and IKE protocols, contains several vulnerabilities that can lead to denial of service conditions. CVE-2026-50721 and CVE-2026-50722 describe DoS attacks via RSA-SHA1 authentication payloads in IKEv1 and IKEv2 respectively. CVE-2026-12413 involves a DoS caused by malformed fragmentation in IKEv2. CVE-2026-14957 is an assertion failure triggered by a badly formatted X.509 certificate, crashing the libreswan daemon. These vulnerabilities affect Red Hat Enterprise Linux 10.0 Extended Update Support and related variants. Red Hat has released security updates to remediate these issues as detailed in advisory RHSA-2026:55449.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service by crashing the libreswan daemon or disrupting IPsec VPN tunnels. This impacts the availability of secure network communications relying on libreswan. There is no indication of remote code execution or data compromise. No known exploits in the wild have been reported.
Mitigation Recommendations
Red Hat has released security updates for libreswan in Red Hat Enterprise Linux 10.0 Extended Update Support to fix these vulnerabilities. Users should apply the update as described in Red Hat advisory RHSA-2026:55449. Patch status is confirmed by the vendor advisory. No additional mitigation steps are specified or required beyond applying the official 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-2026:55449
- Cve Count
- 4
- Additional Cves
- ["CVE-2026-14957","CVE-2026-50721","CVE-2026-50722"]
- Cvss Version
- null
Threat ID: 6a885f1aacd9273b493f7931
Added to database: 08/21/2026, 14:22:18 UTC
Last enriched: 08/21/2026, 14:29:07 UTC
Last updated: 08/22/2026, 03:51:58 UTC
Views: 3
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