CVE-2026-75508

GraphQL-core: Denial of service via comment tokens bypassing the parser's max_tokens limit

State
Published
Severity
7.5 High
Published
Oct 22, 2026
Updated
Oct 29, 2026
Reserved
Aug 17, 2026

Read the record on cve.org

Description

GraphQL-core is a Python port of the GraphQL.js reference implementation. From 3.2.3 until 3.2.12 and 3.3.0rc1, the parser's max_tokens limit in Parser.advance_lexer counts only non-comment tokens returned after Lexer.lookahead skips comments. Each skipped comment is still allocated as a Token and retained through token.next and token.prev, allowing a highly compressible comment-padded GraphQL document to pass a low token limit while consuming memory. An unauthenticated remote attacker can exhaust worker memory before AST-based depth or complexity controls run. This issue is fixed in versions 3.2.12 and 3.3.0rc1.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HGitHub_M

Weaknesses

  • CWE-400 Uncontrolled Resource Consumption
  • CWE-770 Allocation of Resources Without Limits or Throttling

Affected Products

ProductVersions
graphql-coregraphql-python
  • >= 3.2.3, < 3.2.12Affected
  • >= 3.3.0a3, < 3.3.0rc1Affected

References

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