Public vulnerability disclosure

CVE-2026-121286

Security Advisory 0213

publishedCWE-476

On affected platforms running Arista EOS in multi-agent routing model with BGP Segment Routing Traffic Engineering (SR-TE) address family configured, a BGP peer can send crafted BGP packets to cause the BGP process to restart, disrupting all BGP sessions on the device.

Technical severity6.5 mediumCVSS 3.1 · CNA: Arista
Published2026-11-10Source updated 2026-11-13
Collected2026-11-133 attributed sources

Fixes and workarounds

Workaround

For complete mitigation guidance and assistance, customers are advised to contact the Arista Networks Technical Assistance Center (TAC) for support.

Source: CNA: Arista

Affected products and versions

Affected products, source version ranges and reporting authorities
ProductVersionsAuthority
EOS
Arista Networks
Platforms: 710 Series, 720D Series, 720XP/722XPM Series, 750X Series, 7010TX Series, 7020R/R4 Series, 7130 Series running EOS, 7170 Series, 7050X3/X4 Series, 7060X/X2/X4/X5/X6/XE7 Series, 7260X/X3 Series, 7280R/R2/R3/R4 Series, 7300X/X3 Series, 7320X Series, 7358X4 Series, 7368X4 Series, 7388X5 Series, 7500R/R2/R3 Series, 7800R3/R4 Series, 7700R4 Series, AWE 5000 Series, AWE 7200R Series, ZTX-7200 Series, CloudEOS, cEOS-lab, vEOS-lab, CloudVision eXchange, virtual or physical appliance
≥ 4.36.0F; ≤ 4.36.2F (affected, custom)
≥ 4.35.0F; ≤ 4.35.6M (affected, custom)
≥ 4.34.0F; ≤ 4.34.8M (affected, custom)
≥ 4.33.0F; ≤ 4.33.10M (affected, custom)
≥ 4.32.0F; < 4.33.0F (affected, custom)
≥ 4.22.1F; < 4.32.0F (affected, custom)
Other versions: unaffected
CNA: Arista

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / scoreVectorAuthority
3.1 / 6.5
medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HCNA: Arista
4.0 / 6.0
medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCNA: Arista
4.0 / 6.0
medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/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:XNVD: [email protected]
3.1 / 6.5
medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HNVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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