CVE-2026-76763Network attack vector

Service interruption via unbounded BigInteger coercion

Published Aug 31, 2026 · Updated Aug 31, 2026

Improper numeric coercion in Red Hat build of Quarkus allows remote attackers to interrupt exposed GraphQL services. BigInteger scalar coercion accepts float or string inputs without bounding their magnitude, allocating enormous integers from large exponents. Processing occurs before authorization; a crafted inline float literal can exhaust CPU or JVM memory, causing a hang or crash.

CVSS severity7.5
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper numeric coercion in Red Hat build of Quarkus allows remote attackers to interrupt exposed GraphQL services. BigInteger scalar coercion accepts float or string inputs without bounding their magnitude, allocating enormous integers from large exponents. Processing occurs before authorization; a crafted inline float literal can exhaust CPU or JVM memory, causing a hang or crash.

The record

CVE
CVE-2026-76763
Published
Aug 31, 2026
Updated
Aug 31, 2026
Vendor
389 Directory Server
Product
Red Hat build of Quarkus
Classifications
CWE-1284, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 31, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

389 Directory Server · Red Hat build of QuarkusAffected versions are unavailable in this record.

Published CVSS scores

7.5Red HatCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1284Improper Validation of Specified Quantity in Input
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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