# CVE-2026-71310: rclone: Unbounded HTTP CONNECT Response Headers Can Exhaust rclone Memory

> A malicious proxy can cause rclone to crash by sending oversized HTTP CONNECT response headers, requiring a proxy configuration to exploit.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **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:** 31 Aug 2026
- **Also known as:** BIT-rclone-2026-71310, DEBIAN-CVE-2026-71310, GHSA-xhf4-832v-7xcr, GO-2026-6199, MINI-3r7p-w9cf-wmmc, MINI-464m-jqhj-hjgc, MINI-f6rj-8cmm-5v5c, MINI-g79h-rp7j-xf5v, MINI-jg75-53m6-9795, MINI-qfwf-37fr-q395, MINI-v26j-vhpx-34pf, MINI-vhrv-5xp8-c3cv, UBUNTU-CVE-2026-71310

## What is CVE-2026-71310?

CVE-2026-71310 is a medium-severity denial of service vulnerability in rclone, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

rclone is a command-line program to sync files and directories to and from different cloud storage providers. Prior to 1.75.0, the shared HTTP CONNECT helper in lib/proxy/http.go parses proxy CONNECT responses with http.ReadResponse over an unrestricted buffered reader, allowing a malicious or compromised configured proxy, or an active on-path actor controlling a plaintext HTTP proxy hop, to send oversized headers that grow memory until the rclone process fails. The affected helper is used by FTP and SFTP proxy connections, and SFTP reaches the parser before SSH server authentication, so target host key validation does not constrain a malicious proxy. This issue is fixed in 1.75.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-71310?

4 open source packages ship an affected version, including github.com/rclone/rclone and rclone.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/rclone/rclone` | Go | All versions | 1.75.0 |
| `github.com/rclone/rclone` | Go | All versions | 1.75.0 |
| `github.com/rclone/rclone` | Go | All versions | 1.75.0 |
| `rclone` | Bitnami | All versions | 1.75.0 |

## How do I fix CVE-2026-71310?

Upgrade github.com/rclone/rclone to 1.75.0 or later.

## Is CVE-2026-71310 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-71310 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-71310 and fix it if it is affected.

What it is: CVE-2026-71310 is a medium-severity denial of service vulnerability in rclone, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-71310 exists.

Affected packages and fixed versions:
- github.com/rclone/rclone (Go): affected all versions; fixed in 1.75.0
- github.com/rclone/rclone (Go): affected all versions; fixed in 1.75.0
- github.com/rclone/rclone (Go): affected all versions; fixed in 1.75.0
- rclone (Bitnami): affected all versions; fixed in 1.75.0

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-2026-71310/ (Markdown: https://insights.sbomify.com/CVE-2026-71310/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-71310
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-71310
- OSV: https://osv.dev/vulnerability/CVE-2026-71310

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-71310/
Summaries are generated and may contain mistakes; the official description above is the record.