CVE-2026-21912

mediumpriority · track · 19EPSS 0.001 · 1 %ileDEEUNLUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.11% (1st) EPSS
CVSS 4.7 · medium
Is it mine?
22 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · cert_bund · ncsc_nl

EPSS · scored 2026-10-27

A Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in the method to collect FPC Ethernet firmware statistics of Juniper Networks Junos OS on MX10k Series allows a local, low-privileged attacker executing the 'show system firmware' CLI command to cause an LC480 or LC2101 line card to reset. On MX10k Series systems with LC480 or LC2101 line cards, repeated execution of the 'show system firmware' CLI command can cause the line card to crash and restart. Additionally, some time after the line card crashes, chassisd may also crash and restart, generating a core dump.This issue affects Junos OS on MX10k Series:  * all versions before 21.2R3-S10,  * from 21.4 before 21.4R3-S9,  * from 22.2 before 22.2R3-S7,  * from 22.4 before 22.4R3-S6,  * from 23.2 before 23.2R2-S2,  * from 23.4 before 23.4R2-S3,  * from 24.2 before 24.2R2.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.14.7mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 1 · impact 3.6
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · sirt@juniper.net USexploitability 1.8 · impact 3.6
v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL
v4.06.8mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M/U:Ambersecondary · ENISA EU
v4.06.8mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:Ambersecondary · sirt@juniper.net US
v4.04.3mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:Ambersecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-367USCWE-367US
04

affected products (22)

Products and version ranges known to be affected.

showing 20 of 22
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0017Kwetsbaarheden verholpen in Juniper Networks JunOSNL2026-01-16csaf · ncsc_nlNL

    Juniper heeft kwetsbaarheden verholpen in Junos OS (Specifiek voor SRX en MX Series apparaten).

  • WID-SEC-W-2026-0117Juniper Junos OS, Junos Space: Mehrere SchwachstellenDeutsch2026-01-14csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS und Juniper Junos Space ausnutzen, um falsche Informationen darzustellen, beliebigen Code mit Root-Rechten auszuführen, Daten zu manipulieren, vertrauliche Informationen offenzulegen und einen Denial-of-Service-Zustand zu verursachen.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcert_bundncsc_nlnvdNVDCVE.orgMITRE
published 2026-01-15modified 2026-06-17
08

references (7)

External citations — patches, advisories, analysis.

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