CVE-2026-40476: webonyx graphql-php · Inefficient Algorithmic Complexity
Affects webonyx graphql-phpSource CVE Database V5
Not known to be exploited · CVSS 6.9 Medium : upgrade to 15.31.5 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 50% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 15.31.5
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 17 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade graphql-php and webonyx/graphql-php to 15.31.5.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| webonyxgraphql-php | Affected
| Fixed in
|
GitHubwebonyx/graphql-phppkg:github/webonyx/graphql-phpOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade graphql-php to version 15.31.5 or later, where this inefficiency has been fixed. Since the vendor advisory does not specify any temporary workarounds or alternative mitigations, applying the official fix is the recommended action. Patch status is not explicitly confirmed in the advisory, but the fix is indicated by the version increment.
Description
graphql-go is a Go implementation of GraphQL. In versions 15.31.4 and below, the OverlappingFieldsCanBeMerged validation rule performs O(n²) pairwise comparisons of fields sharing the same response name. An attacker can send a query with thousands of repeated identical fields, causing excessive CPU usage during validation before execution begins. This is not mitigated by existing QueryDepth or QueryComplexity rules. This issue has been fixed in version 15.31.5.