CVE-2026-49017CWE-835

CVE-2026-49017

Medium · published May 27, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
28.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00358 · 28.3th percentile
Weakness
CWE-835 · Loop with Unreachable Exit Condition ('Infinite Loop')
Published
2026-05-27T06:16Z
Affected products (3)
ProductVersionsFixed in
openstack/swift≥ 2.35.1, < 2.35.32.35.3
openstack/swift≥ 2.36.0, < 2.36.22.36.2
openstack/swift≥ 2.37.0, < 2.37.22.37.2
References (5)
EPSS history
Timeline
  • 27 MAY 01:57Z
    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
    cvelistv5