CVE-2021-31649Public exploitNetwork attack vector

Remote code execution via unsafe Redis deserialization

Published Jun 24, 2021 · Updated Aug 3, 2024

Deserialization in JFinal 4.9.08 and earlier allows remote attackers to execute arbitrary code through Redis-cached data. JdkSerializer.valueFromBytes passes bytes returned by Cache.get to ObjectInputStream.readObject without restricting the classes instantiated. Exploitation requires an application configured with JdkSerializer and a Redis key whose stored bytes attackers can replace; gadget execution runs in the application process.

CVSS severity9.8
Critical
EPSS probability1.82%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in JFinal 4.9.08 and earlier allows remote attackers to execute arbitrary code through Redis-cached data. JdkSerializer.valueFromBytes passes bytes returned by Cache.get to ObjectInputStream.readObject without restricting the classes instantiated. Exploitation requires an application configured with JdkSerializer and a Redis key whose stored bytes attackers can replace; gadget execution runs in the application process.

The record

CVE
CVE-2021-31649
Published
Jun 24, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-502
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data

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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