Vuln Signal Radar
public-safe defensive signal
HIGHpublic-safe

CVE-2026-91776

NVD: TypeDeserializerBase._findDeserializer() in FasterXML jackson-databind caches the resolved deserializer under the raw, attacker-supplied type ID. NVD: When name-based polymorphism is configured with a fallback, for example @JsonTypeInfo(use = Id.NAME, defaultImpl = ...), every distinct unrecognized type ID resolves to the same fallback deserializer but is retained as its own key in the _deserializers map. NVD: That map has no configurable bound and lives for the lifetime of the type deserializer, so an attacker who can repeatedly supply fresh unknown type IDs causes monotonic memory retention across requests.

CVSS
7.5
Severity
HIGH
EPSS
0.0045 (37)
KEV
-

Source-published summary

NVD: TypeDeserializerBase._findDeserializer() in FasterXML jackson-databind caches the resolved deserializer under the raw, attacker-supplied type ID. NVD: When name-based polymorphism is configured with a fallback, for example @JsonTypeInfo(use = Id.NAME, defaultImpl = ...), every distinct unrecognized type ID resolves to the same fallback deserializer but is retained as its own key in the _deserializers map. NVD: That map has no configurable bound and lives for the lifetime of the type deserializer, so an attacker who can repeatedly supply fresh unknown type IDs causes monotonic memory retention across requests.

Possible impact

This high severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for high severity review.

Affected context

Affected product or version requires source confirmation.

Remediation / advisory

Remediation reference present; patch status requires confirmation in the linked advisory.

Why it matters

This high severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for high severity review.; CVSS 7.5 (HIGH); EPSS percentile 37; not listed in KEV; Remediation reference present; patch status requires confirmation in the linked advisory; sources: NVD, OSV.

What to verify

Confirm affected product/version, vendor advisory, patch or mitigation, and exposure.

Exposure hint

exposure unknown

Impact tags

明示タグなし

Urgency reasons

CVSS HIGHvendor advisory presentrecent updateremediation reference present

Source-derived note

Summary derived from NVD / OSV description; unsafe procedural detail is not shown.

Redaction metadata

source summary used
True
fallback summary used
False
unsafe procedural detail present
false
raw source displayed
false
public summary redacted
true

Remediation handoff

Public-safe static handoff for human/Codex remediation planning. Scan, patch, external execution, and auto remediation are disabled.

Safety note

This radar shows source-published defensive context only. Exploit procedures, exploit strings, scanner commands, and auto-remediation are not provided.

Official references