# HPACK-indexed cookie fields in Mint HTTP/2 responses bypass max_header_list_size and exhaust client memory

Advisory record · `GHSA-9x8p-qrf4-jq7g`

- **Identifiers:** `GHSA-9x8p-qrf4-jq7g` · `CVE-2026-91043` · `EEF-CVE-2026-91043`
- **State:** Confirmed
- **Severity:** CVSS 8.2 High
- **Critical:** No
- **Weakness (CWE):** [CWE-770](https://cwe.mitre.org/data/definitions/770.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Published:** 28 Sept 2026
- **Updated:** 29 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 Sept 2026, 11:15 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `mint` (Hex): affected `>=1.1.0, <1.10.2`; fixed in `1.10.2`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 8.2 High, CVSS 4.0: `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`, from CNA (EEF)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0042, the 36th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 15:25 UTC: First seen by agentprime
- 31 Oct 2026, 15:25 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/EEF-CVE-2026-91043)

## Sources

- [GitHub Advisory Database: GHSA-9x8p-qrf4-jq7g](https://github.com/advisories/GHSA-9x8p-qrf4-jq7g)
- [OSV: GHSA-9x8p-qrf4-jq7g](https://osv.dev/vulnerability/GHSA-9x8p-qrf4-jq7g)
- <https://github.com/elixir-mint/mint/security/advisories/GHSA-9x8p-qrf4-jq7g>
- <https://cna.erlef.org/cves/CVE-2026-91043.html>
- <https://github.com/elixir-mint/mint/commit/8e0e04680476f90f9f68db4dfeabcbe66dabfc4d>
- <https://github.com/elixir-mint/mint/commit/c7895cb022196c77ec35570c8e873a84393ff4b8>
- <https://github.com/elixir-mint/mint/commit/65a0d61c9eab6b0dedac809de7212515bf506250>
- <https://hex.pm/packages/mint>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-9x8p-qrf4-jq7g>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-9x8p-qrf4-jq7g/>. Everything for agents: <https://agentprime.io/llms.txt>.