Bug 2481759 (CVE-2026-49017)

Summary: CVE-2026-49017 openstack-swift: OpenStack Swift: Denial of Service via truncated aws-chunked PUT request
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: unspecifiedCC: eglynn, jjoyce, jpretori, jschluet, lhh, mburns, mgarciac
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in OpenStack Swift. An authenticated attacker can exploit this vulnerability by sending a specially crafted, truncated `aws-chunked PUT` request body to the `s3api` middleware. This action causes an infinite loop within the `StreamingInput` class, leading to the affected proxy-server worker becoming unresponsive. Consequently, an attacker can exhaust all available proxy-server workers, resulting in a Denial of Service (DoS) for the system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-05-27 03:01:34 UTC 
In OpenStack Swift before 2.36.2 and 2.37.2, s3api middleware enters an infinite loop when processing a truncated aws-chunked PUT request body. The StreamingInput class repeatedly appends an empty buffer and re-reads, causing the proxy-server worker handling the request to become permanently unresponsive with increasing CPU and memory consumption. An authenticated attacker can systematically exhaust all proxy-server workers, resulting in denial of service. The defect was introduced in Swift 2.36.0.