CVE-2020-29557Known exploitationNetwork attack vector

Pre-auth remote code execution via web-interface overflow

Published Jan 29, 2021 · Updated Oct 21, 2025

Buffer overflow in the web interface of D-Link DIR-825 R1 3.0.1 and earlier allows remote attackers to execute arbitrary code. Published sources do not identify the affected request handler, input field, or unchecked operation that overruns the buffer. No authentication or user interaction is required, so any attacker able to reach the management web interface can take control of the router.

CVSS severity9.8
Critical
EPSS probability55.75%
Next 30 days · Nov 1, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in the web interface of D-Link DIR-825 R1 3.0.1 and earlier allows remote attackers to execute arbitrary code. Published sources do not identify the affected request handler, input field, or unchecked operation that overruns the buffer. No authentication or user interaction is required, so any attacker able to reach the management web interface can take control of the router.

The record

CVE
CVE-2020-29557
Published
Jan 29, 2021
Updated
Oct 21, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-119, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsShadowserver observations through Sep 28, 2026. Gaps indicate unavailable data.
Sep 22, 2026Sep 28, 2026
View daily counts
Reporting dayUnique IPs
Sep 22, 2026Unavailable
Sep 23, 2026Unavailable
Sep 24, 2026Unavailable
Sep 25, 2026Unavailable
Sep 26, 2026Unavailable
Sep 27, 20261
Sep 28, 20261
Latest reporting daySep 28, 2026
Latest daily unique IPs1
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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