CVE-2021-22118

Local file access and overwrite via temp-directory collision

Published May 27, 2021 · Updated Aug 3, 2024

Privilege escalation in Spring Framework 5.2.0 through 5.2.14 and 5.3.0 through 5.3.6 allows local users to access or overwrite files. WebFlux's SynchronossPartHttpMessageReader and DefaultPartHttpMessageReader use temporary storage directories that can collide across reader instances. A locally authenticated user who recreates the directory can read or modify uploaded files or replace arbitrary files with multipart data.

CVSS severity7.8
High
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in Spring Framework 5.2.0 through 5.2.14 and 5.3.0 through 5.3.6 allows local users to access or overwrite files. WebFlux's SynchronossPartHttpMessageReader and DefaultPartHttpMessageReader use temporary storage directories that can collide across reader instances. A locally authenticated user who recreates the directory can read or modify uploaded files or replace arbitrary files with multipart data.

The record

CVE
CVE-2021-22118
Published
May 27, 2021
Updated
Aug 3, 2024
Vendor
Spring
Product
Spring Framework
Classifications
CWE-668, CWE-269, T1005, T1565.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 27, 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=Spring Framework versions 5.2.x prior to 5.2.15 and versions 5.3.x prior to 5.3.7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Spring · Spring Frameworkversion=Spring Framework versions 5.2.x prior to 5.2.15 and versions 5.3.x prior to 5.3.7

Published CVSS scores

7.8NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-668Exposure of Resource to Wrong Sphere
CWE-269Improper Privilege Management
T1005Data from Local System
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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