# CVE-2026-71190: Denial of service in Swift

> Unauthenticated attackers can cause denial of service in OpenStack Swift proxy servers via crafted Accept headers triggering catastrophic regex backtracking.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **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-2026-71190, GHSA-4jj7-q8c5-78g4, UBUNTU-CVE-2026-71190

## What is CVE-2026-71190?

CVE-2026-71190 is a high-severity denial of service vulnerability in OpenStack Swift, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In OpenStack Swift through 2.38.0, the proxy server Accept header parser contains a regular expression vulnerable to catastrophic backtracking (ReDoS). The "qdtext" pattern (?:[^"]|\\.)* allows an unauthenticated remote attacker to send a crafted Accept header that causes exponential CPU consumption in the proxy worker. A payload of 32 backslash-character pairs exceeds 30 seconds of CPU time. No authentication is required. Repeated requests can exhaust all proxy worker threads, resulting in a complete denial of service.

Weakness: CWE-1333 (Inefficient Regular Expression Complexity)

## Which versions are affected by CVE-2026-71190?


## How do I fix CVE-2026-71190?

Upgrade to a fixed version.

## Is CVE-2026-71190 being exploited?

There is no known exploitation of CVE-2026-71190 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-71190 and fix it if it is affected.

What it is: CVE-2026-71190 is a high-severity denial of service vulnerability in OpenStack Swift, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-71190 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-2026-71190/ (Markdown: https://insights.sbomify.com/CVE-2026-71190/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-71190
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-71190
- OSV: https://osv.dev/vulnerability/CVE-2026-71190

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-71190/
Summaries are generated and may contain mistakes; the official description above is the record.