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CVE-2024-39554· NVD / CVE Program· CNA juniper

Junos OS and Junos OS Evolved: BGP multipath incremental calculation is resulting in an rpd crash

A Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to inject incremental routing updates when BGP multipath is enabled, causing rpd to crash and restart, resulting in a Denial of Service (DoS). Since this is a timing issue (race condition), the successful exploitation of this vulnerability is outside the attacker's control.  However, continued receipt and processing of this packet may create a sustained Denial of Service (DoS) condition. On all Junos OS and Junos OS Evolved platforms with BGP multipath enabled, a specific multipath calculation removes the original next hop from the multipath lead routes nexthop-set. When this change happens, multipath relies on certain internal timing to record the update.  Under certain circumstance and with specific timing, this could result in an rpd crash. This issue only affects systems with BGP multipath enabled. This issue affects: Junos OS: * All versions of 21.1 * from 21.2 before 21.2R3-S7, * from 21.4 before 21.4R3-S6, * from 22.1 before 22.1R3-S5, * from 22.2 before 22.2R3-S3, * from 22.3 before 22.3R3-S2, * from 22.4 before 22.4R3, * from 23.2 before 23.2R2. Junos OS Evolved: * All versions of 21.1-EVO, * All versions of 21.2-EVO, * from 21.4-EVO before 21.4R3-S6-EVO, * from 22.1-EVO before 22.1R3-S5-EVO, * from 22.2-EVO before 22.2R3-S3-EVO, * from 22.3-EVO before 22.3R3-S2-EVO, * from 22.4-EVO before 22.4R3-EVO, * from 23.2-EVO before 23.2R2-EVO. Versions of Junos OS before 21.1R1 are unaffected by this vulnerability. Versions of Junos OS Evolved before 21.1R1-EVO are unaffected by this vulnerability.

HighCVSS 8.2 · v4.0—No exploit Fix available
Published
Jul 10, 2024
Updated
Jun 17, 2026
EPSS
0.4% · 28th percentile
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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
total

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.

Affected systems

VendorProduct
juniperjunos
juniperjunos os evolved

Affected versions

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

  • juniper junos21.1 and later · before 21.2
  • juniper junos21.2
  • juniper junos21.4
  • juniper junos22.1
  • juniper junos22.2
  • juniper junos22.3
  • juniper junos22.4
  • juniper junos23.2
  • juniper junos os evolved21.1 and later · before 21.3
  • juniper junos os evolved21.4
  • juniper junos os evolved22.1
  • juniper junos os evolved22.2
  • juniper junos os evolved22.3
  • juniper junos os evolved22.4
  • juniper junos os evolved23.2

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

    • 21.1 and later · before 21.1*affected · semver
    • 21.2 and later · before 21.2R3-S7affected · semver
    • 21.4 and later · before 21.4R3-S6affected · semver
    • 22.1 and later · before 22.1R3-S5affected · semver
    • 22.2 and later · before 22.2R3-S3affected · semver
    • 22.3 and later · before 22.3R3-S2affected · semver
    • 22.4 and later · before 22.4R3affected · semver
    • 23.2 and later · before 23.2R2affected · semver
    • before 21.1R1not affected · semver

  • Juniper Networks Junos OS Evolved

    • 21.1-EVO and later · before 21.1*-EVOaffected · semver
    • 21.2-EVO and later · before 21.2*-EVOaffected · semver
    • 21.4-EVO and later · before 21.4R3-S6-EVOaffected · semver
    • 22.1-EVO and later · before 22.1R3-S5-EVOaffected · semver
    • 22.2-EVO and later · before 22.2R3-S3-EVOaffected · semver
    • 22.3-EVO and later · before 22.3R3-S2-EVOaffected · semver
    • 22.4-EVO and later · before 22.4R3-EVOaffected · semver
    • 23.2-EVO and later · before 23.2R2-EVOaffected · semver
    • before 21.1R1-EVOnot 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
  • CVE-2023-36847Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary filesKEV
    76This week
  • CVE-2020-1631Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) servicesKEV
    70This week
  • CVE-2025-21590Junos OS: An local attacker with shell access can execute arbitrary codeKEV
    57Plan

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 OS21.1*Vendor (CNA)
Juniper Networks Junos OS21.2R3-S7Vendor (CNA)
Juniper Networks Junos OS21.4R3-S6Vendor (CNA)
Juniper Networks Junos OS22.1R3-S5Vendor (CNA)
Juniper Networks Junos OS22.2R3-S3Vendor (CNA)
Juniper Networks Junos OS22.3R3-S2Vendor (CNA)
Juniper Networks Junos OS22.4R3Vendor (CNA)
Juniper Networks Junos OS23.2R2Vendor (CNA)
Juniper Networks Junos OS Evolved21.1*-EVOVendor (CNA)
Juniper Networks Junos OS Evolved21.2*-EVOVendor (CNA)
Juniper Networks Junos OS Evolved21.4R3-S6-EVOVendor (CNA)
Juniper Networks Junos OS Evolved22.1R3-S5-EVOVendor (CNA)
Juniper Networks Junos OS Evolved22.2R3-S3-EVOVendor (CNA)
Juniper Networks Junos OS Evolved22.3R3-S2-EVOVendor (CNA)
Juniper Networks Junos OS Evolved22.4R3-EVOVendor (CNA)
Juniper Networks Junos OS Evolved23.2R2-EVOVendor (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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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-2024-21601181 days apartJunos OS: SRX Series: Due to an error in processing TCP events flowd will crash
    23Monitor
  • CVE-2023-28984450 days apartJunos OS: QFX Series: The PFE may crash when a lot of MAC addresses are being learned and aged
    21Monitor

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-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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: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.

ATT&CK techniques

—

Noroxi analysis

No Noroxi analysis for this record yet

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Change log

  1. Fix✗ → ✓

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References

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

All records