ZcashFoundation Zebra up to 6.x Mempool protection mechanism

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.00+

Summaryinfo

A vulnerability was found in ZcashFoundation Zebra up to 6.x and classified as problematic. Affected by this issue is some unknown functionality of the component Mempool. Executing a manipulation can lead to protection mechanism. This vulnerability is registered as CVE-2026-123556. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in ZcashFoundation Zebra up to 6.x. This vulnerability affects an unknown code of the component Mempool. The manipulation with an unknown input leads to a protection mechanism vulnerability. The CWE definition for the vulnerability is CWE-693. The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product. As an impact it is known to affect availability. CVE summarizes:

ZcashFoundation Zebra from 4.5.0 before 7.0.0 contains a protection mechanism failure that bans honest peers by scoring mempool lock-time rejections at the ban threshold. Attackers can broadcast transactions locked until the current height right after each block, causing lagging nodes to ban honest relaying peers for 24 hours or until restart.

The advisory is available at github.com. This vulnerability was named CVE-2026-123556 since 11/06/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 7.0.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Protection mechanism
CWE: CWE-693
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Zebra 7.0.0

Timelineinfo

11/06/2026 CVE reserved
11/08/2026 +2 days Advisory disclosed
11/08/2026 +0 days VulDB entry created
11/08/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CNA: VulnCheck
CVE: CVE-2026-123556 (🔒)

GCVE (CVE): GCVE-0-2026-123556
GCVE (VulDB): GCVE-100-432730

Entryinfo

Created: 11/08/2026 03:23
Changes: 11/08/2026 03:23 (76)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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