Vulnerability · Published May 27, 2026 · Assigned by mitre
CVE-2026-49017
High 7.1
In plain English
A high-severity infinite loop in Swift from OpenStack. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | swift | 2.35.1-0+deb13u2 | DEBIAN-CVE-2026-49017 |
| Debian:14 | swift | 2.37.1-4 | DEBIAN-CVE-2026-49017 |
| PyPI | swift | no fix listed | GHSA-g7jq-j257-rww2 |
| PyPI | swift | no fix listed | GHSA-g7jq-j257-rww2 |
| PyPI | swift | no fix listed | PYSEC-2026-3080 |
| Ubuntu:25.10 | swift | no fix listed | UBUNTU-CVE-2026-49017 |
| Ubuntu:26.04:LTS | swift | 2.37.1-0ubuntu2.1 | UBUNTU-CVE-2026-49017 |
| Ubuntu:26.04:LTS | swift | 2.37.1-0ubuntu2.1 | USN-8821-1 |
Affected products (as reported)
Weakness: CWE-835 · Vector: 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