Evidence used
- No CISA KEV confirmation is currently recorded.
- Exploitation requires an existing local or physical foothold with privileges.
- EPSS is 0.17% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-33793High confidence
Junos OS and Junos OS Evolved: When an unsigned Python op script configuration is present, a local low privileged user can compromise the system
Juniper Networks · Junos OS
8.5HighCVSS 4.0
Within 7 days
Patch availableHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:Medium, lowered one band.downgradedsince 16 Apr 2026
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Juniper Networks Junos OS and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Patch available01
What, why and how
An Execution with Unnecessary Privileges vulnerability in the User Interface (UI) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privileged attacker to gain root privileges, thus compromising the system. When a configuration that allows unsigned Python op scripts is present on the device, a non-root user is able to execute malicious op scripts as a root-equivalent user, leading to privilege escalation. This issue affects Junos OS: * All versions before 22.4R3-S7, * from 23.2 before 23.2R2-S4, * from 23.4 before 23.4R2-S6, * from 24.2 before 24.2R1-S2, 24.2R2, * from 24.4 before 24.4R1-S2, 24.4R2; Junos OS Evolved: * All versions before 22.4R3-S7-EVO, * from 23.2 before 23.2R2-S4-EVO, * from 23.4 before 23.4R2-S6-EVO, * from 24.2 before 24.2R2-EVO, * from 24.4 before 24.4R1-S1-EVO, 24.4R2-EVO.
What
An Execution with Unnecessary Privileges vulnerability in the User Interface (UI) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privileged attacker to gain root privileges, thus compromising the system. When a configuration that allows unsigned Python op scripts is present on the device, a non-root user is able to execute malicious op scripts as a root-equivalent user, leading to privilege escalation. This issue affects Junos OS: * All versions before 22.4R3-S7, * from 23.2 before 23.2R2-S4, * from 23.4 before 23.4R2-S6, * from 24.2 before 24.2R1-S2, 24.2R2, * from 24.4 before 24.4R1-S2, 24.4R2; Junos OS Evolved: * All versions before 22.4R3-S7-EVO, * from 23.2 before 23.2R2-S4-EVO, * from 23.4 before 23.4R2-S6-EVO, * from 24.2 before 24.2R2-EVO, * from 24.4 before 24.4R1-S1-EVO, 24.4R2-EVO.
Why
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.
What
An Execution with Unnecessary Privileges vulnerability in the User Interface (UI) of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privileged attacker to gain root privileges, thus compromising the system. When a configuration that allows unsigned Python op scripts is present on the device, a non-root user is able to execute malicious op scripts as a root-equivalent user, leading to privilege escalation. This issue affects Junos OS: * All versions before 22.4R3-S7, * from 23.2 before 23.2R2-S4, * from 23.4 before 23.4R2-S6, * from 24.2 before 24.2R1-S2, 24.2R2, * from 24.4 before 24.4R1-S2, 24.4R2; Junos OS Evolved: * All versions before 22.4R3-S7-EVO, * from 23.2 before 23.2R2-S4-EVO, * from 23.4 before 23.4R2-S6-EVO, * from 24.2 before 24.2R2-EVO, * from 24.4 before 24.4R1-S1-EVO, 24.4R2-EVO.
Why
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
How
An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- local access → Execution with Unnecessary Privileges → gain additional privileges
- Attack surface
- Local
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Not a CVSS 4.0 base metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-250 ↗
CWE-250: Execution with Unnecessary Privileges. The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:L/AU:Y/R:U/V:C/RE:M/U:AmberCommon Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SALowSubsequent-system availability: A successful attack can cause a limited loss.- Post-exploitation / living off the land
- The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Affected
- Fixed
- The following software releases have been updated to resolve this specific issue:
- Junos OS Evolved: 22.4R3-S7-EVO, 23.2R2-S4-EVO, 23.4R2-S6-EVO, 24.2R2-EVO, 24.4R1-S1-EVO, 24.4R2-EVO, 25.2R1-EVO and all subsequent releases.
- Junos OS: 22.4R3-S7, 23.2R2-S4, 23.4R2-S6, 24.2R1-S2, 24.2R2, 24.4R1-S2, 24.4R2, 25.2R1 and all subsequent releases.
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 9 Apr 2026 · Last source change 16 Apr 2026, 15:14 UTC · CWE-250 · Execution with Unnecessary Privileges
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-21095
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Mitigation reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.