# CVE-2026-71191: Missing authorization in Swift

> Attackers can read arbitrary objects via unsigned headers in presigned URLs, bypassing signature validation in OpenStack Swift S3API.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 5 Aug 2026
- **Updated:** 6 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-71191, GHSA-hqwm-h3rj-hvcf, UBUNTU-CVE-2026-71191

## What is CVE-2026-71191?

CVE-2026-71191 is a medium-severity missing authorization vulnerability in OpenStack Swift, published on 5 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

In OpenStack Swift through 2.38.0, S3API middleware does not enforce that semantic x-amz-* headers are covered by the SigV4 signature on presigned URL requests. An attacker who obtains a presigned PUT URL can inject an unsigned X-Amz-Copy-Source header, causing Swift to perform a server-side copy from an arbitrary source object using the signer's authorization context. The attacker can read any object the signer has access to, provided the target project_id, container name, and object name are known. This affects all deployments using the default s3_acl=false configuration.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-71191?


## How do I fix CVE-2026-71191?

Apply the vendor's patch.

## Is CVE-2026-71191 being exploited?

There is no known exploitation of CVE-2026-71191 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-71191 and fix it if it is affected.

What it is: CVE-2026-71191 is a medium-severity missing authorization vulnerability in OpenStack Swift, published on 5 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-71191 in the wild and no public exploit code.

Affected product: OpenStack Swift. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-71191/ (Markdown: https://insights.sbomify.com/CVE-2026-71191/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-71191
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-71191
- OSV: https://osv.dev/vulnerability/CVE-2026-71191

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-71191/
Summaries are generated and may contain mistakes; the official description above is the record.