An Improper Check for Unusual or Exceptional Conditions vulnerability combined with Improper Handling of Exceptional Conditions in Juniper Networks Junos OS on QFX Series and PTX Series allows an unauthenticated network based attacker to cause increased FPC CPU utilization by sending specific IP packets which are being VXLAN encapsulated leading to a partial Denial of Service (DoS). Continued receipted of these specific traffic will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on QFX Series: All versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S3, 19.4R3-S1; 20.1 versions prior to 20.1R2, 20.1R3; 20.2 versions prior to 20.2R2, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2. Juniper Networks Junos OS on PTX Series: All versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R3-S5; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R2-S1, 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2.
CVE-2021-31361
Score 5.3 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 5.3; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.3
- EG Score
- 5.3(medium)
- EG Risk
- —
- EPSS
- 59.6%
- KEV
- Not listed
Published
October 19, 2021
Last Modified
November 21, 2024
References (2)
- sirt@juniperhttps://kb.juniper.net/JSA11223
- af854a3a-2127-422b-91ae-364da2661108https://kb.juniper.net/JSA11223
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 12× in last 7d / 48× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
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Related CVEs(same CWE)
Same CWE
10 shownCWE-754 · CWE-755
- CVE-2017-20166EG 9.8CRITICAL
- CVE-2009-5043EG 9.8CRITICAL
- CVE-2019-14431EG 9.8CRITICAL
- CVE-2019-12815EG 9.8EPSS 99%CRITICAL
- CVE-2019-0036EG 9.8CRITICAL
- CVE-2018-19991EG 9.8CRITICAL
- CVE-2017-2877EG 9.8CRITICAL
- CVE-2017-5638EG 9.8 KEVEPSS 100%CRITICAL
- CVE-2018-0155NVD 8.6EG 9.0 KEVEPSS 94%HIGH
- CVE-2019-14287EG 8.8EPSS 99%HIGH
Frequently asked(5)
What is CVE-2021-31361?
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Is CVE-2021-31361 actively exploited?
What is the CVSS score of CVE-2021-31361?
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Dependency Blast Radius
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