CVE-2021-0260Network attack vector

Unauthenticated SNMP reads and writes via authorization bypass

Published Apr 22, 2021 · Updated Sep 17, 2024

Improper authorization in specified Juniper Networks Junos OS 17.2R1 through 19.3 releases allows remote attackers to access SNMP OIDs. The snmpd service processes incoming SNMP requests on the management routing interface without enforcing the configured SNMP version or authentication method. SNMP and the management instance must be configured; successful requests can read exposed system data or write only OIDs that permit write operations.

CVSS severity7.3
High
EPSS probability0.89%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in specified Juniper Networks Junos OS 17.2R1 through 19.3 releases allows remote attackers to access SNMP OIDs. The snmpd service processes incoming SNMP requests on the management routing interface without enforcing the configured SNMP version or authentication method. SNMP and the management instance must be configured; successful requests can read exposed system data or write only OIDs that permit write operations.

The record

CVE
CVE-2021-0260
Published
Apr 22, 2021
Updated
Sep 17, 2024
Vendor
Juniper Networks
Product
Junos OS
Classifications
CWE-497, CWE-285, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=17.2R1 <17.2*
  2. Affected versionversion=17.3 <17.3R3-S9
  3. Affected versionversion=17.4 <17.4R2-S12, 17.4R3-S5
  4. Affected versionversion=18.1 <18.1R3-S13
  5. Affected versionversion=18.2 <18.2R3-S8
  6. Affected versionversion=18.3 <18.3R3-S5
  7. Affected versionversion=18.4 <18.4R1-S8, 18.4R2-S5, 18.4R3
  8. Affected versionversion=19.1 <19.1R2
  9. Affected versionversion=19.2 <19.2R1-S6, 19.2R2
  10. Affected versionversion=19.3 <19.3R2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OSversion=17.2R1 <17.2*; version=17.3 <17.3R3-S9; version=17.4 <17.4R2-S12, 17.4R3-S5; version=18.1 <18.1R3-S13; version=18.2 <18.2R3-S8; version=18.3 <18.3R3-S5; version=18.4 <18.4R1-S8, 18.4R2-S5, 18.4R3; version=19.1 <19.1R2; version=19.2 <19.2R1-S6, 19.2R2; version=19.3 <19.3R2

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
7.3Juniper Networks, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-497Exposure of Sensitive System Information to an Unauthorized Control Sphere
CWE-285Improper Authorization
T1190Exploit Public-Facing Application

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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