Juniper Junos OS up to 25.2R1-S2 on SRX Server Certificate Parser improper following of a certificate's chain of trust

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.9$0-$5k0.44-

Summaryinfo

A vulnerability described as problematic has been identified in Juniper Junos OS up to 25.2R1-S2 on SRX. This affects an unknown part of the component Server Certificate Parser. Such manipulation leads to improper following of a certificate's chain of trust. This vulnerability is uniquely identified as CVE-2026-33779. The attack can be launched remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Juniper Junos OS up to 25.2R1-S2 on SRX. It has been rated as problematic. Affected by this issue is an unknown code block of the component Server Certificate Parser. The manipulation with an unknown input leads to a improper following of a certificate's chain of trust vulnerability. Using CWE to declare the problem leads to CWE-296. The product does not follow, or incorrectly follows, the chain of trust for a certificate back to a trusted root certificate, resulting in incorrect trust of any resource that is associated with that certificate. Impacted is confidentiality, integrity, and availability. CVE summarizes:

An Improper Following of a Certificate's Chain of Trust vulnerability in J-Web of Juniper Networks Junos OS on SRX Series allows a PITM to intercept the communication of the device and get access to confidential information and potentially modify it. When an SRX device is provisioned to connect to Security Director (SD) cloud, it doesn't perform sufficient verification of the received server certificate. This allows a PITM to intercept the communication between the SRX and SD cloud and access credentials and other sensitive information. This issue affects Junos OS: * all versions before 22.4R3-S9, * 23.2 versions before 23.2R2-S6, * 23.4 versions before 23.4R2-S7, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R1-S2, 25.2R2.

The weakness was disclosed by Konrad Porzezynski as JSA107823. The advisory is shared for download at kb.juniper.net. This vulnerability is handled as CVE-2026-33779 since 03/23/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/10/2026). The MITRE ATT&CK project declares the attack technique as T1557.003.

Upgrading to version 22.4R3-S9, 23.2R2-S6, 23.4R2-S7, 24.2R2-S3, 24.4R2-S2, 25.2R1-S2 or 25.2R2 eliminates this vulnerability.

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Productinfo

Type

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 5.9

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (juniper): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper following of a certificate's chain of trust
CWE: CWE-296 / CWE-295 / CWE-287
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: Junos OS 22.4R3-S9/23.2R2-S6/23.4R2-S7/24.2R2-S3/24.4R2-S2/25.2R1-S2/25.2R2

Timelineinfo

03/23/2026 CVE reserved
04/10/2026 +17 days Advisory disclosed
04/10/2026 +0 days VulDB entry created
04/10/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: juniper.net

Advisory: JSA107823
Researcher: Konrad Porzezynski
Status: Confirmed

CVE: CVE-2026-33779 (🔒)
GCVE (CVE): GCVE-0-2026-33779
GCVE (VulDB): GCVE-100-356732

Entryinfo

Created: 04/10/2026 06:31
Changes: 04/10/2026 06:31 (80)
Complete: 🔍
Cache ID: 216:E99:103

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