# CVE-2026-82728: Unbounded HTTP/1 status-line and chunk-extension buffering in Mint causes memory-exhaustion DoS

> A malicious HTTP server can exhaust memory in the Mint Elixir client by sending unbounded status lines or chunk extensions, causing a denial of service.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/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:** 4 Sep 2026
- **Updated:** 4 Sep 2026
- **Also known as:** EEF-CVE-2026-82728, GHSA-g83f-2j6r-q6m4

## What is CVE-2026-82728?

CVE-2026-82728 is a high-severity denial of service vulnerability in elixir-mint mint, published on 4 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Allocation of Resources Without Limits or Throttling vulnerability in elixir-mint mint allows a remote HTTP server to exhaust memory on the client host and cause a denial of service.

Two HTTP/1 response-parser states accumulate server data without any cap. In lib/mint/http1.ex, decode_status_line/4 stores the unconsumed data in conn.buffer when the status line is incomplete, and decode_body/5 does the same for an unterminated chunk-extension line. Both wait for a CRLF the server never has to send, and conn.buffer is prepended to every subsequent socket message. The :max_header_list_size budget is wired only into decode_headers/5 and decode_trailer_headers/4, so neither of these states is covered by it. A malicious server, or one reached through an attacker-controlled redirect or a fetched URL, streams bytes indefinitely until the BEAM node is killed by the operating system out-of-memory handler. The chunk-extension variant is reached after a valid status line and a complete, valid header section, so an intermediary inspecting only headers sees an ordinary 200 response.

This issue affects mint: from 0.1.0 before 1.10.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-82728?

1 open source package ship an affected version, including mint.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mint` | Hex | From 0.1.0 | 1.10.0 |

## How do I fix CVE-2026-82728?

Upgrade mint to 1.10.0 or later.

## Is CVE-2026-82728 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82728 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82728 and fix it if it is affected.

What it is: CVE-2026-82728 is a high-severity denial of service vulnerability in elixir-mint mint, published on 4 Sep 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-2026-82728 exists.

Affected packages and fixed versions:
- mint (Hex): affected from 0.1.0; fixed in 1.10.0

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-2026-82728/ (Markdown: https://insights.sbomify.com/CVE-2026-82728/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82728
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82728
- OSV: https://osv.dev/vulnerability/CVE-2026-82728

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82728/
Summaries are generated and may contain mistakes; the official description above is the record.