Resource exhaustion in jackson-databind - CVE-2026-91777
Published: September 22, 2026
Vulnerability identifier: #VU151566
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-91777
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to uncontrolled resource consumption in forward-reference completion in CollectionDeserializer.CollectionReferringAccumulator.resolveForwardReference() and the corresponding map implementation when resolving reverse-order object-ID references during deserialization. A remote attacker can submit JSON containing unresolved identity references followed by definitions of the same IDs in reverse order to cause a denial of service.
Exploitation requires the application to deserialize JSON into an identity-enabled collection or map.
Affected software
jackson-databind
How to mitigate CVE-2026-91777
Install security update from vendor's website.
jackson-databind - addressed in versions 2.18.11, 2.21.7, 2.22.3, 3.1.7, 3.2.3