CVE-2021-22440

File access outside restricted directory via crafted filename

Published Jul 13, 2021 · Updated Aug 3, 2024

Path traversal in Huawei Mate 20 and related smartphones allows attackers to access files outside restricted directories via USB. The affected file-handling code builds a pathname from an external filename without validating that the result remains under the intended restricted parent directory, so traversal sequences reach locations outside that directory. Exploitation requires the attacker to connect the smartphone through USB and can disclose files; the advisory does not report integrity or availability impact.

CVSS severity6.2
Medium
EPSS probability0.21%
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 Huawei Mate 20 and related smartphones allows attackers to access files outside restricted directories via USB. The affected file-handling code builds a pathname from an external filename without validating that the result remains under the intended restricted parent directory, so traversal sequences reach locations outside that directory. Exploitation requires the attacker to connect the smartphone through USB and can disclose files; the advisory does not report integrity or availability impact.

The record

CVE
CVE-2021-22440
Published
Jul 13, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1083
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 13, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.8Huawei PSIRTCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L/E:F/RL:O/RC:C
6.2Huawei PSIRTCVSS:3.1/AV:P/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L

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)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1083File and Directory Discovery

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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