Low severity · published Aug 30, 2026
CVE-2026-81643
Broken access control in AshGraphql subscription batcher applies authorization suppression to only the first notification
2.3
CVSS
0.4%
EPSS
No
On KEV
Description
Incorrect Authorization vulnerability in ash-project ash_graphql delivers GraphQL subscription payloads for records a subscriber is not authorized to see.
In AshGraphql.Subscription.Batcher, do_send/5 resolves the first notification of a batch and filters it with should_send?/1, which drops results whose errors are coded forbidden or not_found or carry no code, precisely so that unauthorized results are not disclosed. The remaining notifications in the batch are read from the process dictionary, re-run through the pipeline, and appended to the outgoing results without that filter. They reach pubsub.publish_subscription/2, and the not is_nil(record) guard drops only nil records, not error-carrying results. Any two qualifying notifications arriving within the default one-second batch interval suffice, and batching is the default path. The fix applies should_send?/1 to the whole batch.
This issue affects ash_graphql: from 1.4.0 before 1.11.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_graphql · ash-project
1.4.0 before 1.11.0; 3cb2c9870d050c7c4bba6c211aaed97d732f7e81 before e8e67f39add2ce0771e6db5f086afe68ba212c57 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-81643
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-81643
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-81643.html
github.com
https://github.com/ash-project/ash_graphql/commit/e8e67f39add2ce0771e6db5f086afe68ba212c57
github.com
https://github.com/ash-project/ash_graphql/security/advisories/GHSA-j684-hch4-q888
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-81643
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