CVE-2026-123558 PUBLISHED

Zebra before 7.0.0 Checkpoint Sync Denial of Service via Cancelled Verifier Rewind

Assigner: VulnCheck
Reserved: 06.11.2026 Published: 08.11.2026 Updated: 08.11.2026

Zebra zebrad before 7.0.0 contains a denial of service vulnerability that allows a malicious peer to stall checkpoint sync by cancelling the verifier rewind after a failed commit. Attackers can serve a forged block with altered authorizing data plus a restart-triggering block, leaving the verifier rejecting honest blocks until restart.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.7

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	ZcashFoundation
Product	zebra
Versions	Default: unaffected affected from 0 to 7.0.0 (excl.) Version 7.0.0 is unaffected

CVE-2026-123558 PUBLISHED

Zebra before 7.0.0 Checkpoint Sync Denial of Service via Cancelled Verifier Rewind

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Product Status

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Problem Types