FKIE_CVE-2026-21903

Vulnerability from fkie_nvd - Published: 2026-01-15 21:16 - Updated: 2026-01-23 19:40
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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.
References
sirt@juniper.nethttps://kb.juniper.net/JSA106022Vendor Advisory
sirt@juniper.nethttps://supportportal.juniper.net/JSA106022Vendor Advisory
Impacted products
Vendor Product Version
juniper junos *
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 22.4
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.4
juniper junos 23.4
juniper junos 23.4
juniper junos 23.4
To clipboard 

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      "value": "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."
    },
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      "lang": "es",
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  "id": "CVE-2026-21903",
  "lastModified": "2026-01-23T19:40:03.190",
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          "valueDensity": "NOT_DEFINED",
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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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.