CVE-2021-0286Network attack vector

Unauthenticated traffic disruption via AFT manager crash

Published Jul 15, 2021 · Updated Sep 16, 2024

Denial of service in affected Juniper Networks Junos OS Evolved releases allows remote attackers to crash the AFT manager with crafted packets. The evo-aftmand-bt or evo-aftmand-zx process mishandles an exceptional condition triggered by the packets and terminates on a signal instead of continuing traffic processing. Each restart interrupts all traffic through the FPC, and continued unauthenticated packet delivery sustains the outage without user interaction.

CVSS severity7.5
High
EPSS probability1.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in affected Juniper Networks Junos OS Evolved releases allows remote attackers to crash the AFT manager with crafted packets. The evo-aftmand-bt or evo-aftmand-zx process mishandles an exceptional condition triggered by the packets and terminates on a signal instead of continuing traffic processing. Each restart interrupts all traffic through the FPC, and continued unauthenticated packet delivery sustains the outage without user interaction.

The record

CVE
CVE-2021-0286
Published
Jul 15, 2021
Updated
Sep 16, 2024
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-703, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=21.1 <21.1R2-EVO
  2. Affected versionversion=unspecified <20.4R2-EVO

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=21.1 <21.1R2-EVO; version=unspecified <20.4R2-EVO

Published CVSS scores

7.8NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:C
7.5Juniper NetworksCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-703Improper Check or Handling of Exceptional Conditions
T1499.004Application or System Exploitation

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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