CVE-2021-2416Network attack vector

Authenticated hang or repeatable crash

Published Oct 20, 2021 · Updated Sep 25, 2024

Routing denial of service in Oracle Communications Session Border Controller 8.4 and 9.0 allows remote authenticated users to crash the SBC. Oracle has not published the affected routing operation or how an HTTP request reaches the failure condition. The request requires high privileges; successful exploitation causes a hang or repeatable crash without reported confidentiality or integrity loss.

CVSS severity4.9
Medium
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Routing denial of service in Oracle Communications Session Border Controller 8.4 and 9.0 allows remote authenticated users to crash the SBC. Oracle has not published the affected routing operation or how an HTTP request reaches the failure condition. The request requires high privileges; successful exploitation causes a hang or repeatable crash without reported confidentiality or integrity loss.

The record

CVE
CVE-2021-2416
Published
Oct 20, 2021
Updated
Sep 25, 2024
Vendor
Oracle Corporation
Product
Oracle Communications Session Border Controller
Classifications
T1499
Attack vector
network
Privileges
admin

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

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Is a vulnerable build present?

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

  1. Affected versionversion=8.4
  2. Affected versionversion=9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Oracle Corporation · Oracle Communications Session Border Controllerversion=8.4; version=9.0

Published CVSS scores

6.8NIST NVDAV:N/AC:L/Au:S/C:N/I:N/A:C
4.9OracleCVSS:3.1/AV:N/AC:L/PR:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
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

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Your stack

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