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TI-2026-17616 Aliases CVE-2026-21916GHSA-x5g9-73r3-vh5h

Junos OS: A low privileged user can escalate their privileges so that they can login as root

Priority LOW 32CWE-61Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local, authenticated attacker with low privileges to escalate their privileges to root which will lead to a complete compromise of the system. When after a user has performed a specific 'file link ...' CLI operation, another user commits (unrelated configuration changes), the first user can login as root. This issue affects Junos OS: * all versions before 23.2R2-S7, * 23.4 versions before 23.4R2-S6, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R2. This issue does not affect versions 25.4R1 or later.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00131 2nd percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 23.2R2-S7, 23.4R2-S6, 24.2R2-S3 +3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OSbefore 23.2R2-S7; 23.4 to before 23.4R2-S6; 24.2 to before 24.2R2-S3; 24.4 to before 24.4R2-S2; 25.2 to before 25.2R223.2R2-S7, 23.4R2-S6, 24.2R2-S3, 24.4R2-S2, 25.2R2, 25.4R1Patch availableCNA
  • Junos OS VendorJuniper Affected before 23.2R2-S7; 23.4 to before 23.4R2-S6; 24.2 to before 24.2R2-S3; 24.4 to before 24.4R2-S2; 25.2 to before 25.2R2 Fixed in 23.2R2-S7, 23.4R2-S6, 24.2R2-S3, 24.4R2-S2, 25.2R2, 25.4R1 Patch available CNA

CPE configurations NVD · 39

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:*before 23.2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:*23.2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:*23.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:*23.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:*23.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:*23.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:*23.2 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2-s2:*:*:*:*:*:*23.2 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2-s3:*:*:*:*:*:*23.2 r2-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2-s4:*:*:*:*:*:*23.2 r2-s4VulnerableJuniper
  • cpe:2.3:o:juniper:junos:*:*:*:*:*:*:*:* Versions before 23.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:* Versions 23.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:* Versions 23.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:* Versions 23.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:* Versions 23.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:* Versions 23.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:* Versions 23.2 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s2:*:*:*:*:*:* Versions 23.2 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s3:*:*:*:*:*:* Versions 23.2 r2-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s4:*:*:*:*:*:* Versions 23.2 r2-s4 Vulnerable ·Juniper
Show 29 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:23.2:r2-s5:*:*:*:*:*:*23.2 r2-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:23.2:r2-s6:*:*:*:*:*:*23.2 r2-s6VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:*23.4VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:*23.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:*23.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:*23.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:*23.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2-s1:*:*:*:*:*:*23.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2-s2:*:*:*:*:*:*23.4 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2-s3:*:*:*:*:*:*23.4 r2-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2-s4:*:*:*:*:*:*23.4 r2-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:23.4:r2-s5:*:*:*:*:*:*23.4 r2-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:-:*:*:*:*:*:*24.2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:*24.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r1-s1:*:*:*:*:*:*24.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r1-s2:*:*:*:*:*:*24.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r2:*:*:*:*:*:*24.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r2-s1:*:*:*:*:*:*24.2 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:24.2:r2-s2:*:*:*:*:*:*24.2 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:*24.4VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:*24.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:*24.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:*24.4 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:r2:*:*:*:*:*:*24.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:24.4:r2-s1:*:*:*:*:*:*24.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:*25.2VulnerableJuniper
cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:*25.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:25.2:r1-s1:*:*:*:*:*:*25.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:25.2:r1-s2:*:*:*:*:*:*25.2 r1-s2VulnerableJuniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s5:*:*:*:*:*:* Versions 23.2 r2-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.2:r2-s6:*:*:*:*:*:* Versions 23.2 r2-s6 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:* Versions 23.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:* Versions 23.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:* Versions 23.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:* Versions 23.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:* Versions 23.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2-s1:*:*:*:*:*:* Versions 23.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2-s2:*:*:*:*:*:* Versions 23.4 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2-s3:*:*:*:*:*:* Versions 23.4 r2-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2-s4:*:*:*:*:*:* Versions 23.4 r2-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:23.4:r2-s5:*:*:*:*:*:* Versions 23.4 r2-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:-:*:*:*:*:*:* Versions 24.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:* Versions 24.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r1-s1:*:*:*:*:*:* Versions 24.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r1-s2:*:*:*:*:*:* Versions 24.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r2:*:*:*:*:*:* Versions 24.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r2-s1:*:*:*:*:*:* Versions 24.2 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.2:r2-s2:*:*:*:*:*:* Versions 24.2 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:* Versions 24.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:* Versions 24.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:* Versions 24.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:* Versions 24.4 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:r2:*:*:*:*:*:* Versions 24.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:24.4:r2-s1:*:*:*:*:*:* Versions 24.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:* Versions 25.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:* Versions 25.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:25.2:r1-s1:*:*:*:*:*:* Versions 25.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:25.2:r1-s2:*:*:*:*:*:* Versions 25.2 r1-s2 Vulnerable ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 23.2R2-S7, 23.4R2-S6, 24.2R2-S3, 24.4R2-S2, 25.2R2, 25.4R1

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-21916
  2. 2026-10-03 Alias added: GHSA-x5g9-73r3-vh5h

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