CVE-2021-34820Network attack vector

Unauthenticated file disclosure via path traversal

Published Jul 19, 2021 · Updated Aug 4, 2024

Path traversal in the Novus HTTP Server in AAT NMS through 1.51.2 allows remote attackers to read sensitive files via HTTP GET requests. The server's request-path handling fails to confine file resolution to the web root, allowing a crafted path to traverse to arbitrary files. No authentication or user interaction is required; the published impact is limited to reading sensitive data, not modifying files or interrupting service.

CVSS severity7.5
High
EPSS probability4.00%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in the Novus HTTP Server in AAT NMS through 1.51.2 allows remote attackers to read sensitive files via HTTP GET requests. The server's request-path handling fails to confine file resolution to the web root, allowing a crafted path to traverse to arbitrary files. No authentication or user interaction is required; the published impact is limited to reading sensitive data, not modifying files or interrupting service.

The record

CVE
CVE-2021-34820
Published
Jul 19, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-22, T1005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

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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