CVE-2026-49017

HIGH

Openstack Swift - Loop with Unreachable Exit Condition ('Infinite Loop')

Title source: rule
STIX 2.1

Description

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.

Scores

CVSS v4 7.1
EPSS 0.0027
EPSS Percentile 18.2%
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-835
Status published
Products (3)
OpenStack/Swift 2.35.1 - 2.35.3
OpenStack/Swift 2.36.0 - 2.36.2
OpenStack/Swift 2.37.0 - 2.37.2
Published May 27, 2026
Tracked Since May 27, 2026