CVE-2026-81636 Query-complexity limit bypass via first/last pagination arguments in AshGraphql enables denial of service
Unauthenticated attackers can bypass query complexity limits in AshGraphql to force unbounded database reads, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-81636?
CVE-2026-81636 is a high-severity denial of service vulnerability in ash-project ash_graphql, published on 30 Aug 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 ash-project ash_graphql allows an unauthenticated client to bypass the configured GraphQL query-complexity limit and force an unbounded database read.
AshGraphql.Graphql.Resolver.query_complexity/3 multiplies child complexity by the requested page size only when the argument map contains :limit (offset pagination). Relay connections and keyset pagination use first and last, which never match that clause and fall through to the catch-all that returns child_complexity + 1. A nested relay query such as posts(first: 500) { edges { node { comments(first: 500) { ... } } } } therefore scores as trivially cheap while materializing the full fan-out, passing an Absinthe max_complexity cap that rejects the equivalent limit-based query. The fix adds first and last clauses clamped to the action's page size.
This issue affects ash_graphql: from 0.16.23 before 1.11.0.
Weakness: CWE-770
Which versions are affected by CVE-2026-81636?
1 open source package ship an affected version, including ash_graphql.
| Package | Affected | Fixed in |
|---|---|---|
ash_graphql Hex | From 0.16.23 | 1.11.0 |
How do I fix CVE-2026-81636?
Upgrade ash_graphql to 1.11.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-81636 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-81636 exists.
Sources
Also known as EEF-CVE-2026-81636, GHSA-mwc4-r9fc-h6mg.