Junos OS: SNMP fails to properly perform authorization checks on incoming received SNMP requests.

published 2021-04-22 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-2879

cvss: 7.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

An improper authorization vulnerability in the Simple Network Management Protocol daemon (snmpd) service of Juniper Networks Junos OS leads an unauthenticated attacker being able to perform SNMP read actions, an Exposure of System Data to an Unauthorized Control Sphere, or write actions to OIDs that support write operations, against the device without authentication. This issue affects: Juniper Networks Junos OS: 17.2 version 17.2R1 and later versions; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S12, 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R1-S8, 18.4R2-S5, 18.4R3; 19.1 versions prior to 19.1R2; 19.2 versions prior to 19.2R1-S6, 19.2R2; 19.3 versions prior to 19.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.

Patch / fix

fixed in 1

Juniper Networks Junos OS 17.3R3-S9, 17.4R2-S12, 17.4R3-S5, 18.1R3-S13, 18.2R3-S8, 18.3R3-S5, 18.4R1-S8, 18.4R2-S5, 18.4R3, 19.1R2, 19.2R1-S6, 19.2R2, 19.3R2

Exploit prediction

0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

Juniper Networks Junos OS

Classification

Weakness

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

References

kb.juniper.net /JSA11151
vendor-advisory

Sources

CVE List CVE-2021-0260
NVD CVE-2021-0260

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Summary