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CVE Record

CVE-2021-2451: Vulnerability in the Oracle Outside In Technology product of Oracle Fusion Middleware (component: Outside I...

Vulnerability in the Oracle Outside In Technology product of Oracle Fusion Middleware (component: Outside In Filters). The supported version that is affected is 8.5.5. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle Outside In Technology. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of Oracle Outside In Technology. Note: Outside In Technology is a suite of software development kits (SDKs). The protocol and CVSS Base Score depend on the software that uses Outside In Technology. The CVSS score assumes that the software passes data received over a network directly to Outside In Technology, but if data is not received over a network the CVSS score may be lower. CVSS 3.1 Base Score 7.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

HighCVSS 7.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

This flaw can let an unauthenticated remote user crash or hang software that uses Oracle Outside In Technology 8.5.5 to process network-delivered content. The business impact is service unavailability, not data theft or data tampering based on the provided sources.

Executive priority

Treat as a high-priority availability risk where internet-facing or partner-facing services process uploaded documents through Outside In. Prioritize exposed business-critical workflows first; internal-only or trusted-input deployments may be lower urgency.

Technical view

CVE-2021-2451 affects Oracle Outside In Technology 8.5.5, specifically Outside In Filters. Oracle rates it CVSS 7.5: network, low complexity, no privileges, no user interaction, high availability impact only. The score assumes software receives data over HTTP and passes it directly to the SDK.

Likely exposure

Exposure is most likely in applications embedding Outside In Technology 8.5.5 and processing attacker-controlled files or content received over HTTP. Risk may be lower where input is local, trusted, or not directly passed into the SDK.

Exploitation context

The source bundle says the issue is easily exploitable by an unauthenticated network attacker over HTTP. It is not listed as KEV, and no provided source states active exploitation in the wild.

Researcher notes

The CVSS depends on the consuming application. The provided evidence identifies the affected SDK version and DoS outcome, but not a specific vulnerable host product, fixed version, or active exploitation status.

Mitigation direction

  • Review Oracle July 2021 CPU guidance for CVE-2021-2451 and apply the vendor-recommended update.
  • Inventory applications and products embedding Oracle Outside In Technology 8.5.5.
  • Reduce exposure of HTTP services that pass untrusted content directly into Outside In.
  • Add monitoring for repeated parser crashes, hangs, and service restarts.

Validation and detection

  • Confirm whether Oracle Outside In Technology 8.5.5 exists in deployed applications or vendor products.
  • Check whether any HTTP path feeds external content directly into Outside In Filters.
  • Verify remediation status against Oracle July 2021 CPU guidance.
  • Review logs for recurring crashes or hangs in affected document-processing services.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2021-2451 mapping review

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2021-2451Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Oracle CorporationOutside In Technology8.5.5Listed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.