CVE-2026-75508
GraphQL-core: Denial of service via comment tokens bypassing the parser's max_tokens limit
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By GitHub_M
- 2 months later
· 2 months later
Published
- 7 days later
· 7 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Deferred | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.57% · top 52% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
- affected >= 3.2.3, < 3.2.12
- affected >= 3.3.0a3, < 3.3.0rc1
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIgraphql-coreGHSA-r77w-qph3-7vf8 (opens in a new tab)
References (5)
- https://github.com/graphql-python/graphql-core/security/advisories/GHSA-r77w-qph3-7vf8 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/graphql-python/graphql-core/commit/437dea102e92fdf05a2971ca76787c5a5bad875a (opens in a new tab)x_refsource_MISC
- https://github.com/graphql-python/graphql-core/commit/80ef435a1808fbbcc4aaac63ae76771a1c91002d (opens in a new tab)x_refsource_MISC
- https://github.com/graphql-python/graphql-core/releases/tag/v3.2.12 (opens in a new tab)x_refsource_MISC
- https://github.com/graphql-python/graphql-core/releases/tag/v3.3.0rc1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-r77w-qph3-7vf8 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-75508)Record last updated .