7.4

CVE-2021-0259: juniper networks junos os

CVSS: 7.4v3.1HighModified
Published 22-04-2021Last modified 16-09-2024

Vulnerability summary

CVE-2021-0259 is a high (CVSS 7.4) vulnerability in juniper networks junos os. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 30.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.4/10
010
High · v3.1 (CVE.org)
EPSS score
0.38%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 22-04-2021
    PublishedVulnerability first disclosed.
  2. 16-09-2024
    Last modifiedVulnerability information updated.

Description

Due to a vulnerability in DDoS protection in Juniper Networks Junos OS and Junos OS Evolved on QFX5K Series switches in a VXLAN configuration, instability might be experienced in the underlay network as a consequence of exceeding the default ddos-protection aggregate threshold. If an attacker on a client device on the overlay network sends a high volume of specific, legitimate traffic in the overlay network, due to an improperly detected DDoS violation, the leaf might not process certain L2 traffic, sent by spines in the underlay network. Continued receipt and processing of the high volume traffic will sustain the Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on QFX5K Series: 17.3 versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R3-S5; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R2-S8, 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R2-S4, 19.4R3-S1; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2; 20.3 versions prior to 20.3R1-S2, 20.3R2. Juniper Networks Junos OS Evolved on QFX5220: All versions prior to 20.3R2-EVO.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.38%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

0.00 pp

From 0.38% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.38%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Juniper2 products
  • junos17.3 | 17.3:r1 | 17.3:r1-s1 | 17.3:r1-s4 | 17.3:r2 | 17.3:r2-s1 | 17.3:r2-s2 | 17.3:r2-s3 | 17.3:r2-s4 | 17.3:r2-s5 | 17.3:r3 | 17.3:r3-s1 | 17.3:r3-s10 | 17.3:r3-s2 | 17.3:r3-s3 | 17.3:r3-s4 | 17.3:r3-s5 | 17.3:r3-s6 | 17.3:r3-s7 | 17.3:r3-s8 | 17.3:r3-s9 | 17.4 | 17.4:r1 | 17.4:r1-s1 | 17.4:r1-s2 | 17.4:r1-s3 | 17.4:r1-s4 | 17.4:r1-s5 | 17.4:r1-s6 | 17.4:r1-s7 | 17.4:r2 | 17.4:r2-s1 | 17.4:r2-s10 | 17.4:r2-s11 | 17.4:r2-s2 | 17.4:r2-s3 | 17.4:r2-s4 | 17.4:r2-s5 | 17.4:r2-s6 | 17.4:r2-s7 | 17.4:r2-s8 | 17.4:r2-s9 | 17.4:r3 | 17.4:r3-s1 | 17.4:r3-s2 | 17.4:r3-s3 | 17.4:r3-s4 | 18.1 | 18.1:r1 | 18.1:r2 | 18.1:r2-s1 | 18.1:r2-s2 | 18.1:r2-s4 | 18.1:r3 | 18.1:r3-s1 | 18.1:r3-s10 | 18.1:r3-s11 | 18.1:r3-s12 | 18.1:r3-s2 | 18.1:r3-s3 | 18.1:r3-s4 | 18.1:r3-s5 | 18.1:r3-s6 | 18.1:r3-s7 | 18.1:r3-s8 | 18.1:r3-s9 | 18.2 | 18.2:r1 | 18.2:r1-s2 | 18.2:r1-s3 | 18.2:r1-s4 | 18.2:r1-s5 | 18.2:r2 | 18.2:r2-s1 | 18.2:r2-s2 | 18.2:r2-s3 | 18.2:r2-s4 | 18.2:r2-s5 | 18.2:r2-s6 | 18.2:r2-s7 | 18.2:r3 | 18.2:r3-s1 | 18.2:r3-s2 | 18.2:r3-s3 | 18.2:r3-s4 | 18.2:r3-s5 | 18.2:r3-s6 | 18.2:r3-s7 | 18.3 | 18.3:r1 | 18.3:r1-s1 | 18.3:r1-s2 | 18.3:r1-s3 | 18.3:r1-s4 | 18.3:r1-s5 | 18.3:r1-s6 | 18.3:r2 | 18.3:r2-s1 | 18.3:r2-s2 | 18.3:r2-s3 | 18.3:r2-s4 | 18.3:r3 | 18.3:r3-s1 | 18.3:r3-s2 | 18.3:r3-s3 | 18.3:r3-s4 | 18.4 | 18.4:r1 | 18.4:r1-s1 | 18.4:r1-s2 | 18.4:r1-s3 | 18.4:r1-s4 | 18.4:r1-s5 | 18.4:r1-s6 | 18.4:r1-s7 | 18.4:r2 | 18.4:r2-s1 | 18.4:r2-s2 | 18.4:r2-s3 | 18.4:r2-s4 | 18.4:r2-s5 | 18.4:r3 | 18.4:r3-s1 | 18.4:r3-s2 | 18.4:r3-s3 | 18.4:r3-s4 | 18.4:r3-s5 | 19.1 | 19.1:r1 | 19.1:r1-s1 | 19.1:r1-s2 | 19.1:r1-s3 | 19.1:r1-s4 | 19.1:r1-s5 | 19.1:r2 | 19.1:r2-s1 | 19.1:r3 | 19.1:r3-s1 | 19.1:r3-s2 | 19.1:r3-s3 | 19.2 | 19.2:r1 | 19.2:r1-s1 | 19.2:r1-s2 | 19.2:r1-s3 | 19.2:r1-s4 | 19.2:r1-s5 | 19.2:r2 | 19.2:r2-s1 | 19.2:r3 | 19.2:r3-s1 | 19.3 | 19.3:r1 | 19.3:r1-s1 | 19.3:r2 | 19.3:r2-s1 | 19.3:r2-s2 | 19.3:r2-s3 | 19.3:r2-s4 | 19.3:r2-s5 | 19.3:r3 | 19.3:r3-s1 | 19.4:r1 | 19.4:r1-s1 | 19.4:r1-s2 | 19.4:r1-s3 | 19.4:r2 | 19.4:r2-s1 | 19.4:r2-s2 | 19.4:r2-s3 | 19.4:r3 | 20.1:r1 | 20.1:r1-s1 | 20.1:r1-s2 | 20.1:r1-s3 | 20.1:r1-s4 | 20.2:r1 | 20.2:r1-s1 | 20.2:r1-s2 | 20.2:r1-s3 | 20.3:r1 | 20.3:r1-s1
  • junos_os_evolved18.3:r1 | 19.1:r1 | 19.1:r2 | 19.2:r1 | 19.2:r2 | 19.3:r1 | 19.3:r2 | 20.1:r1 | 20.1:r2 | 20.2:r1 | 20.2:r2 | 20.3:r1
Juniper networks2 products
  • junos os≥ 17.3, < 17.3R3-S11 | ≥ 17.4, < 17.4R3-S5 | ≥ 18.1, < 18.1R3-S13 | ≥ 18.2, < 18.2R2-S8, 18.2R3-S8 | ≥ 18.3, < 18.3R3-S5 | ≥ 18.4, < 18.4R1-S8, 18.4R2-S6, 18.4R3-S6 | ≥ 19.1, < 19.1R3-S4 | ≥ 19.2, < 19.2R1-S6, 19.2R3-S2 | ≥ 19.3, < 19.3R3-S2 | ≥ 19.4, < 19.4R2-S4, 19.4R3-S1 | ≥ 20.1, < 20.1R2 | ≥ 20.2, < 20.2R2 | ≥ 20.3, < 20.3R1-S2, 20.3R2
  • junos os evolved≥ unspecified, < 20.3R2-EVO

2 vendors · 4 products

References

1 links