7.5

CVE-2021-0264: juniper networks junos os

CVSS: 7.5v3.1HighModified
Published 22-04-2021Last modified 16-09-2024
Open JSON

Vulnerability summary

CVE-2021-0264 is a high (CVSS 7.5) vulnerability in juniper networks junos os. EPSS estimates a 0.98% chance of exploitation in the next 30 days, higher than 61.5% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
0.98%
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

A vulnerability in the processing of traffic matching a firewall filter containing a syslog action in Juniper Networks Junos OS on MX Series with MPC10/MPC11 cards installed, PTX10003 and PTX10008 Series devices, will cause the line card to crash and restart, creating a Denial of Service (DoS). Continued receipt and processing of packets matching the firewall filter can create a sustained Denial of Service (DoS) condition. When traffic hits the firewall filter, configured on lo0 or any physical interface on the line card, containing a term with a syslog action (e.g. 'term <name> then syslog'), the affected line card will crash and restart, impacting traffic processing through the ports of the line card. This issue only affects MX Series routers with MPC10 or MPC11 line cards, and PTX10003 or PTX10008 Series packet transport routers. No other platforms or models of line cards are affected by this issue. Note: This issue has also been identified and described in technical service bulletin TSB17931 (login required). This issue affects: Juniper Networks Junos OS on MX Series: 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R3-S2; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2. Juniper Networks Junos OS Evolved on PTX10003, PTX10008: All versions prior to 20.4R2-EVO. This issue does not affect Juniper Networks Junos OS versions prior to 19.3R1.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.98%

Chance of exploitation in the next 30 days

Percentile

62%

Versus all other CVEs

30-day change

0.00 pp

From 0.98% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.98%

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
  • junos19.3 | 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 | 19.4:r1 | 19.4:r1-s1 | 19.4:r1-s2 | 19.4:r2 | 19.4:r2-s1 | 19.4:r2-s2 | 19.4:r3 | 19.4:r3-s1 | 20.1:r1 | 20.1:r1-s1 | 20.1:r1-s2 | 20.1:r1-s3 | 20.1:r1-s4 | 20.1:r2 | 20.1:r2-s1 | 20.2:r1 | 20.2:r1-s1 | 20.2:r1-s2 | 20.2:r1-s3 | 20.2:r2 | 20.2:r2-s1 | 20.3:r1 | 20.3:r2 | 20.4:r1
  • 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 | 20.3:r2 | 20.4:r1
Juniper networks2 products
  • junos os≥ 19.3, < 19.3R3-S2 | ≥ 19.4, < 19.4R3-S2 | ≥ 20.1, < 20.1R3 | ≥ 20.2, < 20.2R2-S2, 20.2R3 | ≥ 20.3, < 20.3R3 | ≥ 20.4, < 20.4R2
  • junos os evolved≥ unspecified, < 20.4R2-EVO

2 vendors · 4 products

References

2 links