Skip to content
Noroxi
NVD / CVE Program· CNA juniper

CVE-2024-21605: Junos OS: SRX 300 Series: Specific link local traffic causes a control plane overload

Noroxi assessment

Priority: Monitor (action score 28/100)

  • 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: 0.29% (FIRST EPSS).
  • Someone on the same network segment can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Juniper Networks Junos OS 21.2R3-S6, 22.1R3-S4, 22.2R3-S2.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Juniper Networks Junos OS 21.2R3-S6, 22.1R3-S4, 22.2R3-S2 or later.

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 Exposure of Resource to Wrong Sphere vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on SRX 300 Series allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS). Specific valid link-local traffic is not blocked on ports in STP blocked state but is instead sent to the control plane of the device. This leads to excessive resource consumption and in turn severe impact on all control and management protocols of the device. This issue affects Juniper Networks Junos OS: * 21.2 version 21.2R3-S3 and later versions earlier than 21.2R3-S6; * 22.1 version 22.1R3 and later versions earlier than 22.1R3-S4; * 22.2 version 22.2R2 and later versions earlier than 22.2R3-S2; * 22.3 version 22.3R2 and later versions earlier than 22.3R3-S1; * 22.4 versions earlier than 22.4R2-S2, 22.4R3; * 23.2 versions earlier than 23.2R1-S1, 23.2R2. This issue does not affect Juniper Networks Junos OS 21.4R1 and later versions of 21.4.

HighCVSS 7.1 · v4.0—No exploit Fix available
Published
Apr 12, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 22th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · juniper
6.5
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:3.1/AV:A/AC:L/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
  • A fix has been released

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

Follow CVE-2024-21605

When you'll hear from us

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

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for juniper records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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.

We use this product, ask for help

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
junipersrx300
junipersrx320
junipersrx340
junipersrx345
junipersrx380

Affected versions

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

  • juniper junos21.2
  • juniper junos22.1
  • juniper junos22.2
  • juniper junos22.3
  • juniper junos22.4
  • juniper junos23.2

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

    • 21.2R3-S3 and later · before 21.2R3-S6affected · semver
    • 22.1R3 and later · before 22.1R3-S4affected · semver
    • 22.2R2 and later · before 22.2R3-S2affected · semver
    • 22.3R2 and later · before 22.3R3-S1affected · semver
    • 22.4 and later · before 22.4R2-S2, 22.4R3affected · semver
    • 23.2 and later · before 23.2R1-S1, 23.2R2affected · semver
    • 21.4 and later · before 21.4*not affected · semver

Same product

juniper: all records

Other highest-scoring records for the same primary product.

  • CVE-2023-36845Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to control an important environment variableKEV
    98Now
  • CVE-2023-36846Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesKEV
    79This week
  • CVE-2023-36844Junos OS: EX Series: A PHP vulnerability in J-Web allows an unauthenticated attacker to control important environment variablesKEV
    78This week

Published before and after this one in the same product

  • ← EarlierCVE-2024-21593Apr 12, 2024 · Junos OS: MX Series with MPC10, MPC11, LC9600, and MX304: A specific MPLS packet will cause a PFE crash
    28Monitor
  • ← EarlierCVE-2024-21598Apr 12, 2024 · Junos OS and Junos OS Evolved: A malformed BGP tunnel encapsulation attribute will lead to an rpd crash
    34Monitor
  • Later →CVE-2024-21609Apr 12, 2024 · Junos OS: MX Series with SPC3, and SRX Series: If specific IPsec parameters are negotiated iked will crash due to a memory leak
    28Monitor

Remediation

Which version to upgrade to

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

Product / packageFixed versionSource
Juniper Networks Junos OS21.2R3-S6Vendor (CNA)
Juniper Networks Junos OS22.1R3-S4Vendor (CNA)
Juniper Networks Junos OS22.2R3-S2Vendor (CNA)
Juniper Networks Junos OS22.3R3-S1Vendor (CNA)
Juniper Networks Junos OS22.4R2-S2, 22.4R3Vendor (CNA)
Juniper Networks Junos OS23.2R1-S1, 23.2R2Vendor (CNA)

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-2024-2159792 days apartJunos OS: MX Series: In an AF scenario traffic can bypass configured lo0 firewall filters
    30Monitor

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).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Someone on the same network segment 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
Adjacent
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-668 · Exposure of Resource to Wrong Sphere

CVSS vector

CVSS:4.0/AV:A/AC:L/AT:N/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:X/R:X/V:X/RE:X/U:X

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

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

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

All records