Skip to content
CVE Tracker
  • Newest CVEsPage
  • Recently added to KEVPage
  • Rising exploitation (EPSS)Page
  • Weekly digestPage
  • StatisticsPage
  • WatchlistPage
  • API documentationPage
  • MCP serverPage
  • Data sourcesPage
  • ChangelogPage
  • AboutPage
  • How it's builtPage
Back

CVE-2021-31375

Junos OS: Receipt of a specific BGP update may cause RPKI policy-checks to be bypassed

High7.2EPSS 0.80%
Published
Updated
Reserved
Assigned by
juniper

Description

An Improper Input Validation vulnerability in routing process daemon (RPD) of Juniper Networks Junos OS devices configured with BGP origin validation using Resource Public Key Infrastructure (RPKI), allows an attacker to send a specific BGP update which may cause RPKI policy-checks to be bypassed. This, in turn, may allow a spoofed advertisement to be accepted or propagated. This issue affects: Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S18; 15.1 versions prior to 15.1R7-S9; 17.2 versions prior to 17.2R3-S3; 17.3 versions prior to 17.3R3-S7; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S13; 18.2 versions prior to 18.2R3-S3; 18.3 versions prior to 18.3R3-S1; 18.4 versions prior to 18.4R3; 19.1 versions prior to 19.1R2; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R2.

Scores

CVSS scores of CVE-2021-31375, by who scored it
Scored byCVSSScoreVector
juniperCNA (assigner)3.1High7.2CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:L
NVDNVD · Modified3.1Medium5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS (exploitation in 30 days)
0.80% · top 43% of all CVEs (7 Nov 2026)
Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.2.

Weakness

Affected products

  • Juniper Networks · Junos OS

    • affected 12.3 – < 12.3R12-S18
    • affected 15.1 – < 15.1R7-S9
    • affected 17.2 – < 17.2R3-S3
    • affected 17.3 – < 17.3R3-S7
    • affected 17.4 – < 17.4R2-S9, 17.4R3
    • affected 18.1 – < 18.1R3-S13
    • affected 18.2 – < 18.2R3-S3
    • affected 18.3 – < 18.3R3-S1
    • affected 18.4 – < 18.4R3
    • affected 19.1 – < 19.1R2
    • affected 19.2 – < 19.2R2
    • affected 19.3 – < 19.3R2

What to do

Solution: The following software releases have been updated to resolve this specific issue: 12.3R12-S18, 15.1R7-S9, 17.2R3-S3, 17.3R3-S7, 17.4R2-S9, 17.4R3, 18.1R3-S13, 18.2R3-S3, 18.3R3-S1, 18.4R3, 19.1R2, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.

Workaround: There are no viable workarounds for this issue.

Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

References (1)

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

CVE-2021-31375 badge
[![CVE-2021-31375](https://trackcve.app/badge/CVE-2021-31375.svg)](https://trackcve.app/cve/CVE-2021-31375)

Record last updated .