Cyber Resilience

CVE-2026-33779

Juniper Junos ≤ 22.4

Published
09 April 2026
Modified
17 April 2026
Patch / advisory
View advisory
CVSS Score v4 8.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/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:X/R:X/V:X/RE:M/U:X
EPSS Score 0.0012 2th percentile
Risk Priority 32 floored blend · peak EPSS

Summary

CVE-2026-33779 is a high-severity Improper Following of a Certificate's Chain of Trust (CWE-296) vulnerability in Juniper Junos. Its CVSS base score is 8.3 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Subvert Trust Controls (T1553); ranked at the 2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-17 (Public Key Infrastructure Certificates) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic Failures

EU & UK References

Vulnerability Data

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.…

more

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.

CWE(s)
CWE-296

Related Threats

MITRE ATT&CK Enterprise Techniques

T1553 Subvert Trust Controls Defense Impairment
Adversaries may undermine security controls that will either warn users of untrusted activity or prevent execution of untrusted programs.
attack.mitre.org →
T1553.002 Code Signing Defense Impairment
Adversaries may create, acquire, or steal code signing materials to sign their malware or tools.
attack.mitre.org →
T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
attack.mitre.org →
T1606 Forge Web Credentials Credential Access
Adversaries may forge credential materials that can be used to gain access to web applications or Internet services.
attack.mitre.org →
T1649 Steal or Forge Authentication Certificates Credential Access
Adversaries may steal or forge certificates used for authentication to access remote systems or resources.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-30658Same product: Juniper Junos
CVE-2025-30645Same product: Juniper Junos
CVE-2024-39527Same product: Juniper Junos
CVE-2026-21920Same product: Juniper Junos
CVE-2025-6549Same product: Juniper Junos
CVE-2026-21914Same product: Juniper Junos
CVE-2026-33790Same product: Juniper Junos
CVE-2025-21592Same product: Juniper Junos
CVE-2026-21906Same product: Juniper Junos
CVE-2024-47506Same product: Juniper Junos

Affected Assets

juniper
junos
22.4, 23.2, 23.4, 24.2, 24.4 · ≤ 22.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 12 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

SC-17 Public Key Infrastructure Certificates good match

SC-17 requires proper issuance and management of PKI certificates, which structurally enforces correct chain-of-trust validation.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 mostly match
prevents

Proper service/hardware authentication requires correct certificate chain validation to a trusted root.

ID.RA-09 partial match
prevents

Pre-acquisition authenticity checks may surface certificate issues but do not address runtime chain-following logic.

PR.AA-04 partial match
prevents

Verifying identity assertions includes ensuring certificate chains are followed correctly.

PR.DS-02 partial match
prevents

Protecting data-in-transit commonly depends on TLS certificate chain validation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.24 Use of cryptography mostly match
prevents

Mandates proper use of cryptography including certificate validation and trusted roots.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect missing or incorrect certificate chain validation.

A.8.28 Secure coding partial match
prevents

Secure coding standards address correct certificate chain validation.

A.8.5 Secure authentication partial match
degrades

Requires secure authentication mechanisms that rely on valid certificate chains.

A.8.20 Networks security none match
mitigates

Network security controls often enforce TLS certificate validation.

A.8.21 Security of network services none match
mitigates

Secure network services depend on correct certificate chain validation.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248531 OL 8, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. prevents CWE-296
Oracle Linux 9 (1 rule)
  • V-271604 OL 9, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. prevents CWE-296
RHEL 8 (1 rule)
  • V-230229 RHEL 8, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. prevents CWE-296
RHEL 9 (1 rule)
  • V-258131 RHEL 9, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor. prevents CWE-296

References