CVE-2021-23391

Arbitrary file overwrite via unconfined archive extraction

Published Jun 7, 2021 · Updated Sep 16, 2024

Path traversal in Calipso 0.3.54 and earlier allows local users to overwrite arbitrary files by installing a malicious module archive. The module installer extracts archive entry paths without ensuring their resolved destinations remain inside the intended module directory. Exploitation requires the ability to invoke module installation with a crafted archive and can replace any file writable by the Calipso process.

CVSS severity7.3
High
EPSS probability0.43%
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 Calipso 0.3.54 and earlier allows local users to overwrite arbitrary files by installing a malicious module archive. The module installer extracts archive entry paths without ensuring their resolved destinations remain inside the intended module directory. Exploitation requires the ability to invoke module installation with a crafted archive and can replace any file writable by the Calipso process.

The record

CVE
CVE-2021-23391
Published
Jun 7, 2021
Updated
Sep 16, 2024
Vendor
Calipso Project
Product
Calipso
Classifications
CWE-22, T1565.001
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jun 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

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  1. Affected versionversion=0 <unspecified

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

Calipso Project · Calipsoversion=0 <unspecified

Published CVSS scores

7.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
7.3SnykCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
3.6NIST NVDAV:L/AC:L/Au:N/C:N/I:P/A:P

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)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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