CVE-2021-35041Network attack vector

Unauthenticated denial of service via malformed packets

Published Jun 23, 2021 · Updated Aug 4, 2024

Improper input validation in FISCO-BCOS 2.7.2 allows remote attackers to crash a blockchain node via malformed network packets. The node fails to safely decode continuously delivered packets in an invalid format, allowing memory consumption to grow until the process crashes. The attack requires a malicious network peer but no authentication or user interaction, and the documented consequence is service interruption without confidentiality or integrity impact.

CVSS severity7.5
High
EPSS probability1.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in FISCO-BCOS 2.7.2 allows remote attackers to crash a blockchain node via malformed network packets. The node fails to safely decode continuously delivered packets in an invalid format, allowing memory consumption to grow until the process crashes. The attack requires a malicious network peer but no authentication or user interaction, and the documented consequence is service interruption without confidentiality or integrity impact.

The record

CVE
CVE-2021-35041
Published
Jun 23, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-20, T1498
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NVDAV:N/AC:L/Au:N/C:N/I:N/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.

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1498Network Denial of Service

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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