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NVD / CVE Program· CNA juniper

CVE-2026-33794: Junos OS Evolved: PTX Series: Receipt of repeated ECMP routing updates results in PFE crash

Noroxi assessment

Priority: Monitor (action score 32/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.40% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.
  • Severity is disputed: the assigning authority (CNA) scores it 5.9, NVD 8.2.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

An Improper Check for Unusual or Exceptional Conditions vulnerability in the advanced forwarding toolkit (evo-aftmand) of Juniper Networks Junos OS Evolved on PTX Series allows an unauthenticated network-based attacker generating continuous routing updates, resulting in unilist ECMP routes, to crash the evo-aftmand process on the PFE, leading to a Denial-of-Service (DoS). The conditions required for successful exploitation are based on a sequence of events that are outside an attacker's direct control. Unified list (unilist) ECMP routes are a specific ECMP behavior where multiple equal-cost routes share a single logical next-hop list entry. The router treats them as one route with multiple next hops and load balances traffic across that unified list. Due to an issue processing unilist ECMP routing updates, internal state corruption may occur, especially in large-scale ECMP unilist deployments, leading to the evo-aftmand process crashing, resulting in an evo-aftmand-bx core. Manual intervention is required to recover by rebooting the system or restarting the FPC. This issue affects Junos OS Evolved on PTX : * from 24.4R2-EVO before 24.4R2-S3-EVO; * from 25.2 before 25.2R2-EVO.

HighCVSS 8.2 · v4.0—No exploit No fix recorded
Published
Jul 9, 2026
Updated
Oct 25, 2026
EPSS
0.4% · 35th percentile

Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
32 / 40 · 8.2 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · juniper
5.9
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-33794

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
juniperjunos os evolved
juniperptx1000-72q
juniperptx10000
juniperptx10001
juniperptx10001-36mr
juniperptx100016
juniperptx10002
juniperptx10002-36qdd
juniperptx10002-60c
juniperptx10003
juniperptx10003 160c
juniperptx10003 80c

and 7 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • juniper junos os evolved24.4
  • juniper junos os evolved25.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (juniper). Independent of NVD's CPE analysis and usually ahead of it.

  • Juniper Networks Junos OS Evolved

    • 24.4R2-EVO and later · before 24.4R2-S3-EVOaffected
    • 25.2 and later · before 25.2R2, 25.2R2-EVOaffected

Same product

juniper: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-21902Junos OS Evolved: PTX Series: A vulnerability allows a unauthenticated, network-based attacker to execute code as root
    43Plan
  • CVE-2026-101990Junos OS and Junos OS Evolved: A BGP peer causes an rpd crash when flow-spec routes are re-advertised
    37Monitor
  • CVE-2026-101986Junos OS and Junos OS Evolved: J-Web permits pre-authentication CGI execution
    37Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-33783Apr 9, 2026 · Junos OS Evolved: PTX Series: If SRTE tunnels provisioned via PCEP are present and specific gRPC queries are received evo-aftmand crashes
    28Monitor
  • ← EarlierCVE-2026-33788Apr 9, 2026 · Junos OS Evolved: Local, authenticated attacker can gain privileged access to FPCs
    34Monitor
  • Later →CVE-2026-33803Jul 9, 2026 · Junos OS Evolved: A port which has been inadvertently exposed can be reached by an attacker
    27Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2025-59958273 days apartJunos OS Evolved: PTX Series: When a firewall filter rejects traffic these packets are erroneously sent to the RE
    27Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-754 · Improper Check for Unusual or Exceptional Conditions

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/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:Y/R:U/V:C/RE:M/U:Green

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records