CVE-2026-71192
OpenStack Swift S3API Middleware Authorization Bypass
Description
In OpenStack Swift through 2.38.0, the S3API middleware does not sanitize Swift-native control headers (X-Copy-From, X-Copy-From-Account) from S3 API requests when s3_acl=true. An attacker can inject these headers into a signed PUT request targeting their own bucket, causing Swift to perform a server-side copy from another tenant's private object. The source object authorization is bypassed because the S3API middleware has already authorized the request against the destination. The attacker can read any object whose project_id, container name, and object name are known, regardless of the source object's ACLs or ownership. This requires the non-default s3_acl=true configuration.
INFO
Published Date :
Aug. 5, 2026, 6:16 a.m.
Last Modified :
Aug. 5, 2026, 6:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Disable the s3_acl configuration option.
- Apply vendor-supplied patches for OpenStack Swift.
- Restrict access to Swift S3API middleware.
- Sanitize control headers in S3 API requests.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-71192.
| URL | Resource |
|---|---|
| https://launchpad.net/bugs/2158733 | |
| https://openwall.com/lists/oss-security/2026/07/28/26 | |
| https://security.openstack.org/ossa/OSSA-2026-030.html |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-71192 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-71192
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-71192 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-71192 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Aug. 05, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://opendev.org/openstack/swift', 'vendor': 'OpenStack', 'product': 'Swift', 'versions': [{'status': 'affected', 'version': '2.18.0', 'lessThan': '2.35.4', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.36.0', 'lessThan': '2.36.3', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.37.0', 'lessThan': '2.37.3', 'versionType': 'semver'}, {'status': 'affected', 'version': '2.38.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description In OpenStack Swift through 2.38.0, the S3API middleware does not sanitize Swift-native control headers (X-Copy-From, X-Copy-From-Account) from S3 API requests when s3_acl=true. An attacker can inject these headers into a signed PUT request targeting their own bucket, causing Swift to perform a server-side copy from another tenant's private object. The source object authorization is bypassed because the S3API middleware has already authorized the request against the destination. The attacker can read any object whose project_id, container name, and object name are known, regardless of the source object's ACLs or ownership. This requires the non-default s3_acl=true configuration. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/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 Added CWE CWE-863 Added Reference https://launchpad.net/bugs/2158733 Added Reference https://openwall.com/lists/oss-security/2026/07/28/26 Added Reference https://security.openstack.org/ossa/OSSA-2026-030.html