CVE-2020-36939Public exploitNetwork attack vectorHinoki check available

Unauthenticated file read via disabled path protection

Published Jan 27, 2026 · Updated Jan 27, 2026

Path traversal in avalanche123 Cassandra Web 0.5.0 allows remote attackers to read arbitrary files through crafted URL paths. Sinatra static-file handling receives encoded ../ segments because the application disables Rack::Protection, allowing resolution outside app/public. The server binds to localhost by default, so remote reachability requires a changed bind address or proxy exposure; readable files are limited to the server process permissions and can include Cassandra credentials passed on its command line.

CVSS severity8.7
High
EPSS probability2.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Path traversal in avalanche123 Cassandra Web 0.5.0 allows remote attackers to read arbitrary files through crafted URL paths. Sinatra static-file handling receives encoded ../ segments because the application disables Rack::Protection, allowing resolution outside app/public. The server binds to localhost by default, so remote reachability requires a changed bind address or proxy exposure; readable files are limited to the server process permissions and can include Cassandra credentials passed on its command line.

The record

CVE
CVE-2020-36939
Published
Jan 27, 2026
Updated
Jan 27, 2026
Vendor
avalanche123
Product
Cassandra Web
Classifications
CWE-22, T1190, T1005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 27, 2026Record 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=0.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

avalanche123 · Cassandra Webversion=0.5.0

Published CVSS scores

8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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.

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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 exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1190Exploit Public-Facing Application
T1005Data from Local System

Public exploit references

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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