CVE intelligence and bounded remediation

CVE-2020-2756 — Vulnerability in the Java SE, Java SE Embedded product of Oracle Java SE (component: Serialization)

Medium CVSS 4.3

Vulnerability in the Java SE, Java SE Embedded product of Oracle Java SE (component: Serialization). Supported versions that are affected are Java SE: 7u251, 8u241, 11.0.6 and 14; Java SE Embedded: 8u241. Difficult to exploit vulnerability allows unauthenticated attacker with network access via multiple protocols to compromise Java SE, Java SE Embedded. Successful attacks of this vulnerability can result in unauthorized ability to cause a partial denial of service (partial DOS) of Java SE, Java SE Embedded. Note: Applies to client and server deployment of Java. This vulnerability can be exploited through sandboxed Java Web Start applications and sandboxed Java applets. It can also be exploited by supplying data to APIs in the specified Component without using sandboxed Java Web Start applications or sandboxed Java applets, such as through a web service. CVSS 3.0 Base Score 3.7 (Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L).

Severity
Medium
CVSS
4.3 (2.0)
Published
2020-04-15
CISA KEV
Not currently listed
Ecosystem
java/maven
Weaknesses
CWE-502, CWE-755

Affected products

  • oracle / jdk / 1.7.0
  • oracle / jdk / 1.8.0
  • oracle / jdk / 11.0.6
  • oracle / jdk / 14.0.0
  • oracle / jre / 1.7.0
  • oracle / jre / 1.8.0

Showing 6 representative product identities from 135 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Unsafe deserialization and object reconstruction

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Check exposure

  • Inventory serialization formats accepted from requests, queues, caches, files, cookies, and cross-service messages.
  • Trace whether untrusted input can select classes, types, callbacks, constructors, or object hooks during decoding.
  • Identify signing, schema validation, trust-boundary, and compatibility settings for each decoder.

Remediate safely

  • Replace native object deserialization with a data-only format and explicit schema validation.
  • If replacement is not immediate, use a safe decoder with a minimal type allowlist and disable polymorphic or executable hooks.
  • Update the affected library and add inert tests for unknown types, extra fields, malformed nesting, and unsigned data.

Authoritative sources

Complete CVE record and remediation plan

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