Bug 2550633

Summary: CVE-2026-77207 libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS [fedora-all]
Product: [Fedora] Fedora Reporter: TEJ RATHI <trathi>
Component: libreswanAssignee: Paul Wouters <paul.wouters>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: dueno, paul.wouters, shebburn
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---Flags: fedora-admin-xmlrpc: mirror+
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["b724f81d-ef88-4220-9693-759cea272fca"]}
Fixed In Version: Doc Type: ---
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Clone Of: Environment:
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Regression: --- Mount Type: ---
Documentation: --- CRM:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2550258    

Description TEJ RATHI 2026-10-13 15:41:51 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

The Libreswan Project was informed of a Null Pointer Dereference bug in the PKCS#7 handling code for authentication that can result in a denial of service against the libreswan pluto daemon. 

When libreswan decodes an IKE CERT payload of type CERT_PKCS7_WRAPPED_X509, it guards the PKCS#7 blob with SEC_PKCS7ContainsCertsOrCrls() and then iterates the certificate list with SEC_PKCS7GetCertificateList(). The two NSS APIs disagree on a SignedData that carries a CRL but no
certificates: ContainsCertsOrCrls() returns PR_TRUE (there is a CRL), so the guard passes, but GetCertificateList() returns NULL (there are no certificates). This causes libreswan to dereference a null pointer leading to a crash and restart.

An malicious IKE_AUTH packet can trigger this bug, meaning the peer need not be authenticated. Continued attempts to use IKEv2 with such malicious payloads can cause a denial of service. No remote code execution is possible.

Vulnerable versions : 4.7 - 5.4
Not vulnerable      : 5.3.3, 5.4.1