# GraphQL-core: Denial of service via quadratic complexity in the OverlappingFieldsCanBeMerged validation rule Advisory record · `GHSA-vj8h-fx38-h3vc` - **Identifiers:** `GHSA-vj8h-fx38-h3vc` · `CVE-2026-75507` - **State:** Confirmed - **Severity:** CVSS 7.5 High - **Critical:** No - **Weakness (CWE):** [CWE-400](https://cwe.mitre.org/data/definitions/400.html) · [CWE-407](https://cwe.mitre.org/data/definitions/407.html) - **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md) - **Published:** 22 Oct 2026 - **Updated:** 22 Oct 2026 - **Reviewed by a person:** No Published by the GitHub Advisory Database at 22 Oct 2026, 16:26 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Affected packages - `graphql-core` (PyPI): affected `>=3.0.0, <3.2.12 || >=3.3.0a1, <3.3.0rc1`; fixed in `3.2.12`, `3.3.0rc1` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > GraphQL-core (PyPI package graphql-core) versions 3.0.0 up to but not including 3.2.12, and 3.3.0a1 up to but not including 3.3.0rc1, are vulnerable. A single small, highly compressible query can make the OverlappingFieldsCanBeMerged validation rule run for minutes on one CPU core, enabling denial of service by unauthenticated remote requests. Upgrade to graphql-core 3.2.12 or 3.3.0rc1, which cap the number of field comparisons per document. Until then, reject oversized documents after decompression before they reach validation. Written 1 Nov 2026. ## 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 - 7.5 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`, from CNA (GitHub_M) - **CISA KEV:** Not listed. - **EPSS:** 0.0060, the 48th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days. ## Timeline - 31 Oct 2026, 14:08 UTC: First seen by agentprime - 31 Oct 2026, 14:08 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-vj8h-fx38-h3vc) ## Sources - [GitHub Advisory Database: GHSA-vj8h-fx38-h3vc](https://github.com/advisories/GHSA-vj8h-fx38-h3vc) - [OSV: GHSA-vj8h-fx38-h3vc](https://osv.dev/vulnerability/GHSA-vj8h-fx38-h3vc) - - - - - - 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 (), 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: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .