Affects Juniper Junos (widely deployed network OS); unauthenticated BGP input can cause DoS or RCE—high-impact on enterprise and provider networks.
CVE-2026-33789
Stack overflow in Junos rpd via crafted BGP updates (BMP enabled) -> DoS/RCE
Is CVE-2026-33789 being exploited?
Not confirmed. CVE-2026-33789 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.69% probability of exploitation in the next 30 days.
How severe is CVE-2026-33789?
CVE-2026-33789 is rated Critical with a CVSS score of 9.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-33789?
Yes. A fix has been recorded for CVE-2026-33789. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-33789 affect?
CVE-2026-33789 affects Juniper Junos OS, Juniper Junos OS Evolved, rpd (routing protocol daemon) with BMP enabled. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-33789?
Apply Juniper advisory patch immediately; disable BMP or restrict BGP peers until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
An unauthenticated BGP peer can cause denial of service and potential root-level command execution via crafted BGP updates when BMP is enabled.
Immediate action required
- affected< 23.2R2-S7.7
- affected>= 23.4 and < 23.4R2-S8.13
- affected>= 24.2 and < 24.2R2-S5.5
- affected>= 24.4 and < 24.4R2-S5
- affected>= 25.2 and < 25.2R2-S2
- affected>= 25.4 and < 25.4R1-S3
- affected>= 26.2 and < 26.2R1-S2
- affected< 23.2R2-S7.7-EVO
- affected>= 23.4 and < 23.4R2-S8.11-EVO
- affected>= 24.2 and < 24.2R2-S5.6-EVO
- affected>= 24.4 and < 24.4R2-S5-EVO
- affected>= 25.2 and < 25.2R2-S2-EVO
- affected>= 25.4 and < 25.4R1-S3-EVO
- affected>= 26.2 and < 26.2R1-S2-EVO
- affected23.4X100
- affected>= 25.2X100 and < 25.2X100-D35-EVO
- affected>= 25.4X300 and < 25.4X300-D40-EVO
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.