JetBrains Junie up to 1.6.3 Prompt Injection Protection code injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k1.66

Summaryinfo

A vulnerability, which was classified as critical, has been found in JetBrains Junie up to 1.6.3. Affected is an unknown function of the component Prompt Injection Protection. This manipulation causes code injection. This vulnerability appears as CVE-2026-123851. The attack may be initiated remotely. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in JetBrains Junie up to 1.6.3 and classified as critical. Affected by this vulnerability is an unknown functionality of the component Prompt Injection Protection. The manipulation with an unknown input leads to a code injection vulnerability. The CWE definition for the vulnerability is CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In JetBrains Junie GitHub Action before 1.6.4 prompt injection protection could be bypassed via HTML-encoded characters

The advisory is shared at jetbrains.com. This vulnerability is known as CVE-2026-123851 since 11/06/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059 for this issue.

Upgrading to version 1.6.4 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (JetBrains): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Junie 1.6.4

Timelineinfo

11/06/2026 Advisory disclosed
11/06/2026 +0 days CVE reserved
11/06/2026 +0 days VulDB entry created
11/06/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: jetbrains.com
Status: Confirmed

CNA: JetBrains
CVE: CVE-2026-123851 (🔒)

GCVE (CVE): GCVE-0-2026-123851
GCVE (VulDB): GCVE-100-432013

Entryinfo

Created: 11/06/2026 17:39
Changes: 11/06/2026 17:39 (63)
Complete: 🔍
Cache ID: 216::103

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