Vulnerability-Lookup

GHSA-H3C8-3472-7V7G

Vulnerability from github – Published: 2026-01-15 21:31 – Updated: 2026-01-15 21:31

Details

Subscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart. The issue was not seen when YANG packages for the specific sensors were installed.

This issue affects Junos OS:

all versions before 22.4R3-S7,
23.2 version before 23.2R2-S4,
23.4 versions before 23.4R2.

Severity ?

6.5 (Medium)


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

7.1 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L

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{
  "affected": [],
  "aliases": [
    "CVE-2026-21903"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-121"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-15T21:16:05Z",
    "severity": "HIGH"
  },
  "details": "A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker,\u00a0authenticated\u00a0with low privileges to cause a Denial-of-Service (DoS).\n\n\n\nSubscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart.\nThe issue was not seen when YANG packages for the specific sensors were installed. \n\n\n\nThis issue affects Junos OS:\u00a0\n\n\n\n  *  all versions before 22.4R3-S7,\n  *  23.2 version before 23.2R2-S4,\n  *  23.4 versions before 23.4R2.",
  "id": "GHSA-h3c8-3472-7v7g",
  "modified": "2026-01-15T21:31:48Z",
  "published": "2026-01-15T21:31:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21903"
    },
    {
      "type": "WEB",
      "url": "https://kb.juniper.net/JSA106022"
    },
    {
      "type": "WEB",
      "url": "https://supportportal.juniper.net/JSA106022"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-21903 (GCVE-0-2026-21903)

Vulnerability from cvelistv5 – Published: 2026-01-15 20:18 – Updated: 2026-01-15 21:12

Title

Junos OS: Subscribing to telemetry sensors at scale causes all FPCs to crash

Summary

A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS). Subscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart. The issue was not seen when YANG packages for the specific sensors were installed. This issue affects Junos OS: * all versions before 22.4R3-S7, * 23.2 version before 23.2R2-S4, * 23.4 versions before 23.4R2.

Severity ?

6.5 (Medium)


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

7.1 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L

CWE

CWE-121 - Stack-based Buffer Overflow

Assigner

juniper

References

URL

Tags

	https://supportportal.juniper.net/JSA106022	vendor-advisory
	https://kb.juniper.net/JSA106022	vendor-advisory

Impacted products

	Vendor	Product	Version
	Juniper Networks	Junos OS	Affected: 0 , < 22.4R3-S7 (semver) Affected: 23.2 , < 23.2R2-S4 (semver) Affected: 23.4 , < 23.4R2 (semver)

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

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GHSA-H3C8-3472-7V7G

CVE-2026-21903 (GCVE-0-2026-21903)

Tags

Sightings

Nomenclature