CVE-2026-42793 Atom table exhaustion via attacker-controlled GraphQL SDL names in absinthe
Unauthenticated attackers can crash the Erlang VM by exhausting the atom table via malicious GraphQL SDL names in Absinthe.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-42793?
CVE-2026-42793 is a high-severity denial of service vulnerability in absinthe-graphql absinthe, published on 8 May 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 absinthe-graphql absinthe allows unauthenticated denial of service via atom table exhaustion when parsing attacker-controlled GraphQL SDL.
Multiple Blueprint.Draft.convert/2 implementations in Absinthe's SDL language modules call String.to_atom/1 on attacker-controlled names from parsed GraphQL SDL documents, including directive names, field names, type names, and argument names. Because atoms are never garbage-collected and the BEAM atom table has a fixed limit (default 1,048,576), each unique name permanently consumes one slot. An attacker can exhaust the atom table by submitting SDL documents containing enough unique names, causing the Erlang VM to abort with system_limit and taking down the entire node.
Any application that passes attacker-controlled GraphQL SDL through Absinthe's parser is exposed — for example, a schema-upload endpoint, a federation gateway that ingests remote SDL, or any developer tool that runs the parser over user-supplied documents.
This issue affects absinthe: from 1.5.0 before 1.10.2.
Weakness: CWE-770
Which versions are affected by CVE-2026-42793?
3 open source packages ship an affected version, including absinthe. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
absinthe Hex | From 1.5.0 | 1.10.2 |
absinthe Hex | From 1.5.0 | 1.10.2 |
absinthe Hex | From 1.5.0 | 1.10.2 |
Products include Absinthe-Graphql Absinthe.
How do I fix CVE-2026-42793?
Upgrade absinthe to 1.10.2 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-2026-42793 being exploited?
There is no known exploitation of CVE-2026-42793 in the wild and no public exploit code.
Other vulnerabilities in absinthe-graphql absinthe
Sources
Also known as EEF-CVE-2026-42793, GHSA-qf4g-9fqq-mmm7.