Io.smallrye/smallrye-graphql: smallrye graphql: unauthenticated denial of service via large exponent float literals
Summary
| CVE | CVE-2026-76763 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-31 14:17:23 UTC |
| Updated | 2026-09-01 21:03:04 UTC |
| Description | A flaw was found in SmallRye GraphQL. The number scalar coercion for BigInteger does not properly validate the magnitude of float or string inputs. An unauthenticated remote attacker can exploit this by sending a GraphQL query containing a large exponent float literal. This can lead to the allocation of extremely large BigInteger objects, causing CPU exhaustion or an OutOfMemoryError, resulting in a denial of service. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.003540000 probability, percentile 0.283750000 (date 2026-09-03)
Problem Types: CWE-1284 | CWE-1284 Improper Validation of Specified Quantity in Input
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Build Of Quarkus | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-76763 | [email protected] | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank Arpit Jain for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-08-19T16:46:42.274Z | Reported to Red Hat. |
| CNA | 2026-08-31T11:58:30.899Z | Made public. |
Workarounds
CNA: To mitigate this issue, applications exposing SmallRye GraphQL endpoints should implement validation and bounding of the precision or exponent for incoming numeric literals before they reach scalar coercion. Additionally, limiting the JVM heap size can help constrain the impact of OutOfMemoryError, though it will not prevent CPU exhaustion. Implementing rate-limiting or timeouts on the GraphQL endpoint can also reduce exposure. Using GraphQL variables instead of inline literals for numeric inputs is a safe alternative, as variables follow a secure parsing path.