CVE-2023-2538Network attack vector

TLS private-key disclosure via forced browsing

Published Jul 5, 2023 · Updated Oct 24, 2024

External file exposure in TYAN S5552 BMC firmware 3.00 allows remote attackers to retrieve the web interface's TLS private key. The web interface serves the certificate's private-key file to unauthenticated forced-browsing requests rather than restricting it as sensitive data. No account is required; abusing the key for an HTTPS man-in-the-middle attack additionally requires a victim to use the interface through an attacker-controlled network path.

CVSS severity4.2
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

External file exposure in TYAN S5552 BMC firmware 3.00 allows remote attackers to retrieve the web interface's TLS private key. The web interface serves the certificate's private-key file to unauthenticated forced-browsing requests rather than restricting it as sensitive data. No account is required; abusing the key for an HTTPS man-in-the-middle attack additionally requires a victim to use the interface through an attacker-controlled network path.

The record

CVE
CVE-2023-2538
Published
Jul 5, 2023
Updated
Oct 24, 2024
Vendor
TYAN Computer Corporation
Product
TYAN S5552 BMC Firmware
Classifications
CWE-552, CAPEC-94, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 5, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 24, 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=3.00

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TYAN Computer Corporation · TYAN S5552 BMC Firmwareversion=3.00

Published CVSS scores

5.8Nozomi Networks Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:L
4.2NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/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-552Files or Directories Accessible to External Parties
CAPEC-94Adversary in the Middle (AiTM)
T1557Adversary-in-the-Middle

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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