CVE-2020-2555 — Access Manager
CRITICALCVE-2020-2555 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability in oracle access manager. It is in CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
Vulnerability in the Oracle Coherence product of Oracle Fusion Middleware (component: Caching,CacheStore,Invocation). Supported versions that are affected are 3.7.1.0, 12.1.3.0.0, 12.2.1.3.0…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2021-11-03. Federal agencies were required to remediate by 2022-05-03.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2020-2555.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-2555 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Vulnerability in the Oracle Coherence product of Oracle Fusion Middleware (component: Caching,CacheStore,Invocation). Supported versions that are affected are 3.7.1.0, 12.1.3.0.0, 12.2.1.3.0 and 12.2.1.4.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via T3 to compromise Oracle Coherence. Successful attacks of this vulnerability can result in takeover of Oracle Coherence. CVSS 3.0 Base Score 9.8 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).
Affected Products
access manageroraclecoherenceoraclecommerce platformoraclecommunications diameter signaling routeroraclehealthcare data repositoryoraclerapid planningoracleResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
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Detection & mitigation playbook
Vendor / applianceDetect
Inventory every oracle access manager deployment and check each version against the affected-products list above.
Remediation status
No patch has shipped for CVE-2020-2555 yet — track the oracle access manager advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2020-2555 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.