CVE-2026-33797 (GCVE-0-2026-33797)
Vulnerability from cvelistv5 – Published: 2026-04-09 21:31 – Updated: 2026-04-09 21:31
VLAI?
Title
Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset
Summary
An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).
An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:
* 25.2 versions before 25.2R2
This issue doesn't not affected Junos OS versions before 25.2R1.
This issue affects Junos OS Evolved:
* 25.2-EVO versions before 25.2R2-EVO
This issue doesn't not affected Junos OS Evolved versions before 25.2R1-EVO.
eBGP and iBGP are affected.
IPv4 and IPv6 are affected.
Severity ?
CWE
- CWE-20 - Improper Input Validation
Assigner
References
| URL | Tags | ||||
|---|---|---|---|---|---|
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Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Juniper Networks | Junos OS |
Affected:
25.2 , < 25.2R2
(semver)
Unaffected: 0 , < 25.2R1 (semver) |
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Date Public ?
2026-04-08 16:00
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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.
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