CVE-2020-20267Network attack vector

Resolver process crash via crafted packet

Published May 11, 2021 · Updated Aug 4, 2024

Memory corruption in the /nova/bin/resolver process in MikroTik RouterOS before 6.47 allows remote authenticated users to crash the process. The resolver handles a crafted packet with an invalid memory access that raises signal 11 and terminates the process. Exploitation requires authenticated network access, and the demonstrated consequence is interruption of the resolver service.

CVSS severity6.5
Medium
EPSS probability1.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in the /nova/bin/resolver process in MikroTik RouterOS before 6.47 allows remote authenticated users to crash the process. The resolver handles a crafted packet with an invalid memory access that raises signal 11 and terminates the process. Exploitation requires authenticated network access, and the demonstrated consequence is interruption of the resolver service.

The record

CVE
CVE-2020-20267
Published
May 11, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.0NIST National Vulnerability DatabaseAV:N/AC:L/Au:S/C:N/I:N/A:P
6.5NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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