Bug 2483504 (CVE-2026-48840)

Summary: CVE-2026-48840 exim: Exim: Information disclosure via mishandled short payloads in proxy configurations
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Exim. In certain proxy configurations, Exim mishandles short data payloads. This can lead to the disclosure of uninitialized stack memory values to a remote client, potentially exposing sensitive information.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2484717, 2484718    
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Description OSIDB Bzimport 2026-05-30 03:01:19 UTC
Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.