CVE-2021-20783Network attack vector

Administrator action hijacking via crafted web page

Published Jul 28, 2021 · Updated Aug 3, 2024

Cross-site request forgery in all versions of SoftBank Optical BB unit E-WMTA2.3 allows remote attackers to perform administrator operations. Published advisories do not identify the affected management endpoint or state whether origin checks or request tokens are missing. Exploitation requires an administrator to remain logged in and view a crafted page, which can send unintended requests with the active session.

CVSS severity5.4
Medium
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site request forgery in all versions of SoftBank Optical BB unit E-WMTA2.3 allows remote attackers to perform administrator operations. Published advisories do not identify the affected management endpoint or state whether origin checks or request tokens are missing. Exploitation requires an administrator to remain logged in and view a crafted page, which can send unintended requests with the active session.

The record

CVE
CVE-2021-20783
Published
Jul 28, 2021
Updated
Aug 3, 2024
Vendor
SoftBank Corp.
Product
Optical BB unit E-WMTA2.3
Classifications
CWE-352, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=all versions

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

SoftBank Corp. · Optical BB unit E-WMTA2.3version=all versions

Published CVSS scores

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
4.0JPCERT/CCAV:N/AC:H/Au:N/C:N/I:P/A:P
5.4JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:L

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

CWE-352Cross-Site Request Forgery (CSRF)
T1204.001Malicious Link

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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