Bug 2512093 (CVE-2026-48521)

Summary: CVE-2026-48521 envoy: envoy: HTTP/3 null transport socket options dereference during connection-pool selection
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: kaycoth, security-response-team
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Deadline: 2026-08-26   

Description OSIDB Bzimport 2026-08-06 15:01:37 UTC 
An abnormal process termination during ALPN-based HTTP/3 connection-pool selection. Envoy could dereference null transport socket options while selecting the HTTP/3 connectivity grid. The fix checks that the options exist before accessing HTTP/1.1 proxy information.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H (5.9)

Embargoed until 2026-08-26 13:00 GMT per Envoy upstream disclosure. PSIRTSUPT-21132.