CVE-2021-32803

Arbitrary file overwrite via poisoned directory cache

Published Aug 3, 2021 · Updated Aug 3, 2024

Path traversal in npm node-tar allows local users to create or overwrite arbitrary files by extracting a crafted archive. A directory entry primes the extraction cache, then a same-named symlink replaces it; cached mkdir handling skips the symlink check for later entries. Exploitation requires an application or user to extract the untrusted archive, after which writes can escape the intended destination.

CVSS severity8.2
High
EPSS probability7.80%
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 npm node-tar allows local users to create or overwrite arbitrary files by extracting a crafted archive. A directory entry primes the extraction cache, then a same-named symlink replaces it; cached mkdir handling skips the symlink check for later entries. Exploitation requires an application or user to extract the untrusted archive, after which writes can escape the intended destination.

The record

CVE
CVE-2021-32803
Published
Aug 3, 2021
Updated
Aug 3, 2024
Vendor
npm
Product
node-tar
Classifications
CWE-22, CWE-59, CWE-23, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 3, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=< 3.2.3
  2. Affected versionversion=>= 4.0.0, < 4.4.15
  3. Affected versionversion=>= 5.0.0, < 5.0.7
  4. Affected versionversion=>= 6.0.0, < 6.1.2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

npm · node-tarversion=< 3.2.3; version=>= 4.0.0, < 4.4.15; version=>= 5.0.0, < 5.0.7; version=>= 6.0.0, < 6.1.2

Published CVSS scores

8.2GitHubCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-59Improper Link Resolution Before File Access ('Link Following')
CWE-23Relative Path Traversal
T1204.002User Execution: Malicious File

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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