TI-2026-85852 Aliases CVE-2026-123311 GHSA-3vff-55hr-vh4w

Command execution in JetBrains IntelliJ IDEA via Markdown preview

LOW 25CWE-1021Published 2026-11-06 · Updated 2026-11-07

Key facts

Attack vector: Local
Privileges required: None
User interaction: Required
Attack complexity: High
Impact type: Spoofing
Confidentiality · integrity · availability: Low · High · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-1021.

Summary

JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 is affected. Improper restriction of rendered UI layers (CWE-1021) lets a hidden run control in the Markdown preview execute commands. A local attacker with no privileges can trigger this when a user interacts with the preview.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 command execution via a hidden run control in the Markdown preview was possible

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00141 3rd percentileScored 2026-11-07

Fix Fixed IntelliJ IDEA (JetBrains): 2026.3, 2026.2.4

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

Vendor	Product	Affected versions	Fixed in	Status	Source
JetBrains	IntelliJ IDEA	before 2026.3, 2026.2.4	2026.3, 2026.2.4	Patch available	CNA

IntelliJ IDEA VendorJetBrains Affected before 2026.3, 2026.2.4 Fixed in 2026.3, 2026.2.4 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:jetbrains:intellij_idea::::::::	—	—	JetBrains

cpe:2.3:a:jetbrains:intellij_idea:*:*:*:*:*:*:*:* Versions — — ·JetBrains

Remediation

Update IntelliJ IDEA to version 2026.3 or 2026.2.4, which fix this flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Fix · CNA IntelliJ IDEA (JetBrains) Fixed in 2026.3, 2026.2.4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-11-06
JetBrains IntelliJ IDEA 2026.3, 2026.2.4
6 records Highest priority Priority LOW 6 LOW
Other records, highest priority first
- TI-2026-85835 Code execution in IntelliJ IDEA via Terraform tool path settingPriority LOW 35
- TI-2026-85848 Server-side request forgery in JetBrains IntelliJ IDEAPriority LOW 32
- TI-2026-85850 Cross-site scripting in JetBrains IntelliJ IDEA Markdown previewPriority LOW 27
Show all 6 records →

Timeline

2026-11-06 Threatist record created from CVE-2026-123311
2026-11-06 Alias added: GHSA-3vff-55hr-vh4w
2026-11-07 CISA SSVC decision points changed

References

Other 1

https://www.jetbrains.com/privacy-security/issues-fixed/

TI-2026-45031 Deserialization of untrusted data in JetBrains TeamCity KEVCVSS 3.1CRITICAL 9.8
TI-2024-18053 In JetBrains TeamCity before 2023.11.4 authentication bypass allowing to perform admin actions was possible KEVCVSS 3.1CRITICAL 9.8
TI-2023-22884 In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible KEVCVSS 3.1CRITICAL 9.8
TI-2024-18054 In JetBrains TeamCity before 2023.11.4 path traversal allowing to perform limited admin actions was possible KEVCVSS 3.1HIGH 7.3
TI-2024-15905 In JetBrains TeamCity before 2023.11.3 authentication bypass leading to RCE was possible CVSS 3.1CRITICAL 9.8
TI-2024-24589 Insufficiently protected credentials in JetBrains IntelliJ IDEA CVSS 3.1CRITICAL 9.3

See all 787 →

Sources

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