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TI-2021-11495 Aliases CVE-2021-31351GHSA-j3ff-rvrx-2j9x

Junos OS: MX Series: Receipt of specific packet on MS-MPC/MS-MIC causes line card reset

Priority LOW 35CWE-754Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

An Improper Check for Unusual or Exceptional Conditions in packet processing on the MS-MPC/MS-MIC utilized by Juniper Networks Junos OS allows a malicious attacker to send a specific packet, triggering the MS-MPC/MS-MIC to reset, causing a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue only affects specific versions of Juniper Networks Junos OS on MX Series: 17.3R3-S11; 17.4R2-S13; 17.4R3 prior to 17.4R3-S5; 18.1R3-S12; 18.2R2-S8, 18.2R3-S7, 18.2R3-S8; 18.3R3-S4; 18.4R3-S7; 19.1R3-S4, 19.1R3-S5; 19.2R1-S6; 19.3R3-S2; 19.4R2-S4, 19.4R2-S5; 19.4R3-S2; 20.1R2-S1; 20.2R2-S2, 20.2R2-S3, 20.2R3; 20.3R2, 20.3R2-S1; 20.4R1, 20.4R1-S1, 20.4R2; 21.1R1; This issue does not affect any version of Juniper Networks Junos OS prior to 15.1X49-D240;

Why it matters now

EPSS 0.0102 63rd percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 17.3, 17.4R3, 20.4R2-S1 +3

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS—17.3, 17.4R3Patch availableCNA
JuniperJunos OS17.3R3-S11; 18.1R3-S12; 18.3R3-S4; 18.4R3-S7; 19.1R3-S4, 19.1R3-S5; 19.2R1-S6; 19.3R3-S2; 19.4R3-S2; 20.1R2-S1; 20.2R3; 20.3R2; 17.4R2-S13 and later; 18.2R2-S8, 18.2R3-S7 and later; 18.4R1-S8, 18.4R2-S7 and later; 19.4R2-S4 and later; 20.2R2-S2 and later; 20.3R1-S2 and later; 20.4 to before 20.4R2-S1, 20.4R3; 21.1 to before 21.1R1-S1, 21.1R220.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2Patch availableCNA
  • Junos OS VendorJuniper Affected — Fixed in 17.3, 17.4R3 Patch available CNA
  • Junos OS VendorJuniper Affected 17.3R3-S11; 18.1R3-S12; 18.3R3-S4; 18.4R3-S7; 19.1R3-S4, 19.1R3-S5; 19.2R1-S6; 19.3R3-S2; 19.4R3-S2; 20.1R2-S1; 20.2R3; 20.3R2; 17.4R2-S13 and later; 18.2R2-S8, 18.2R3-S7 and later; 18.4R1-S8, 18.4R2-S7 and later; 19.4R2-S4 and later; 20.2R2-S2 and later; 20.3R1-S2 and later; 20.4 to before 20.4R2-S1, 20.4R3; 21.1 to before 21.1R1-S1, 21.1R2 Fixed in 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2 Patch available CNA

CPE configurations NVD · 47

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:17.3:r3-s11:*:*:*:*:*:*17.3 r3-s11VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r2-s13:*:*:*:*:*:*17.4 r2-s13VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r3:*:*:*:*:*:*17.4 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r3-s1:*:*:*:*:*:*17.4 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r3-s2:*:*:*:*:*:*17.4 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r3-s3:*:*:*:*:*:*17.4 r3-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:17.4:r3-s4:*:*:*:*:*:*17.4 r3-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:18.1:r3-s12:*:*:*:*:*:*18.1 r3-s12VulnerableJuniper
cpe:2.3:o:juniper:junos:18.2:r2-s8:*:*:*:*:*:*18.2 r2-s8VulnerableJuniper
cpe:2.3:o:juniper:junos:18.2:r3-s7:*:*:*:*:*:*18.2 r3-s7VulnerableJuniper
  • cpe:2.3:o:juniper:junos:17.3:r3-s11:*:*:*:*:*:* Versions 17.3 r3-s11 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r2-s13:*:*:*:*:*:* Versions 17.4 r2-s13 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r3:*:*:*:*:*:* Versions 17.4 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r3-s1:*:*:*:*:*:* Versions 17.4 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r3-s2:*:*:*:*:*:* Versions 17.4 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r3-s3:*:*:*:*:*:* Versions 17.4 r3-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:17.4:r3-s4:*:*:*:*:*:* Versions 17.4 r3-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.1:r3-s12:*:*:*:*:*:* Versions 18.1 r3-s12 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.2:r2-s8:*:*:*:*:*:* Versions 18.2 r2-s8 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.2:r3-s7:*:*:*:*:*:* Versions 18.2 r3-s7 Vulnerable ·Juniper
Show 37 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:18.2:r3-s8:*:*:*:*:*:*18.2 r3-s8VulnerableJuniper
cpe:2.3:o:juniper:junos:18.3:r3-s4:*:*:*:*:*:*18.3 r3-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r3-s7:*:*:*:*:*:*18.4 r3-s7VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r3-s4:*:*:*:*:*:*19.1 r3-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r3-s5:*:*:*:*:*:*19.1 r3-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1-s6:*:*:*:*:*:*19.2 r1-s6VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r3-s2:*:*:*:*:*:*19.3 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2-s4:*:*:*:*:*:*19.4 r2-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2-s5:*:*:*:*:*:*19.4 r2-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r3-s2:*:*:*:*:*:*19.4 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r2-s1:*:*:*:*:*:*20.1 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r2-s2:*:*:*:*:*:*20.2 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r2-s3:*:*:*:*:*:*20.2 r2-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r3:*:*:*:*:*:*20.2 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:20.3:r2:*:*:*:*:*:*20.3 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.3:r2-s1:*:*:*:*:*:*20.3 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.4:r1:*:*:*:*:*:*20.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.4:r1-s1:*:*:*:*:*:*20.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.4:r2:*:*:*:*:*:*20.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:21.1:r1:*:*:*:*:*:*21.1 r1VulnerableJuniper
cpe:2.3:h:juniper:mx10:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx10000:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx10003:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx10008:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx10016:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx104:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx150:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx2008:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx2010:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx2020:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx204:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx240:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx40:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx480:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx5:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx80:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
cpe:2.3:h:juniper:mx960:-:*:*:*:*:*:*:*not specified by NVDRunning onJuniper
  • cpe:2.3:o:juniper:junos:18.2:r3-s8:*:*:*:*:*:* Versions 18.2 r3-s8 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.3:r3-s4:*:*:*:*:*:* Versions 18.3 r3-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r3-s7:*:*:*:*:*:* Versions 18.4 r3-s7 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r3-s4:*:*:*:*:*:* Versions 19.1 r3-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r3-s5:*:*:*:*:*:* Versions 19.1 r3-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1-s6:*:*:*:*:*:* Versions 19.2 r1-s6 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r3-s2:*:*:*:*:*:* Versions 19.3 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2-s4:*:*:*:*:*:* Versions 19.4 r2-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2-s5:*:*:*:*:*:* Versions 19.4 r2-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r3-s2:*:*:*:*:*:* Versions 19.4 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r2-s1:*:*:*:*:*:* Versions 20.1 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r2-s2:*:*:*:*:*:* Versions 20.2 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r2-s3:*:*:*:*:*:* Versions 20.2 r2-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r3:*:*:*:*:*:* Versions 20.2 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.3:r2:*:*:*:*:*:* Versions 20.3 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.3:r2-s1:*:*:*:*:*:* Versions 20.3 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.4:r1:*:*:*:*:*:* Versions 20.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.4:r1-s1:*:*:*:*:*:* Versions 20.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.4:r2:*:*:*:*:*:* Versions 20.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:21.1:r1:*:*:*:*:*:* Versions 21.1 r1 Vulnerable ·Juniper
  • cpe:2.3:h:juniper:mx10:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx10000:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx10003:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx10008:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx10016:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx104:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx150:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx2008:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx2010:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx2020:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx204:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx240:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx40:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx480:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx5:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx80:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper
  • cpe:2.3:h:juniper:mx960:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 17.3, 17.4R3
  • Fix · CNA Junos OS (Juniper Networks) Fixed in 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-31351
  2. 2026-10-03 Alias added: GHSA-j3ff-rvrx-2j9x

References

Advisory 1

  • TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
  • TI-2023-18644 Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload and download arbitrary files KEVCVSS 3.1MEDIUM 5.3
  • TI-2023-18640 Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files KEVCVSS 3.1MEDIUM 5.3
See all 792 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences