CVE-2021-35659Network attack vector

Service interruption via undisclosed filter flaw

Published Oct 20, 2021 · Updated Sep 25, 2024

Denial of service in Oracle Outside In Technology 8.5.5 allows remote attackers to hang or repeatedly crash Outside In Filters. Oracle has not disclosed the malformed input, parser, or incorrect operation within the Outside In Filters component that triggers the failure. Network exploitation is unauthenticated only when an embedding application passes attacker-controlled HTTP data to the SDK, and the bounded impact is interruption through a hang or repeatable crash.

CVSS severity7.5
High
EPSS probability1.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in Oracle Outside In Technology 8.5.5 allows remote attackers to hang or repeatedly crash Outside In Filters. Oracle has not disclosed the malformed input, parser, or incorrect operation within the Outside In Filters component that triggers the failure. Network exploitation is unauthenticated only when an embedding application passes attacker-controlled HTTP data to the SDK, and the bounded impact is interruption through a hang or repeatable crash.

The record

CVE
CVE-2021-35659
Published
Oct 20, 2021
Updated
Sep 25, 2024
Vendor
Oracle Corporation
Product
Oracle Outside In Technology
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.5.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle Corporation · Oracle Outside In Technologyversion=8.5.5

Published CVSS scores

7.5Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo