CVE-2023-39737Network attack vector

Unauthorized broadcasts via leaked client secret

Published Oct 24, 2023 · Updated Sep 12, 2024

Sensitive-information exposure in Linecorp Matsuya Line 13.6.1 allows remote attackers to obtain a channel token and send crafted broadcasts. The public CVE record does not identify where or how the Matsuya client secret is exposed. No authentication or user interaction is required; possession of the secret enables token retrieval and unauthorized broadcast-message submission.

CVSS severity8.2
High
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive-information exposure in Linecorp Matsuya Line 13.6.1 allows remote attackers to obtain a channel token and send crafted broadcasts. The public CVE record does not identify where or how the Matsuya client secret is exposed. No authentication or user interaction is required; possession of the secret enables token retrieval and unauthorized broadcast-message submission.

The record

CVE
CVE-2023-39737
Published
Oct 24, 2023
Updated
Sep 12, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 24, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 12, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
8.2CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

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-200Exposure of Sensitive Information to an Unauthorized Actor
T1528Steal Application Access Token

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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