CVE-2020-29322Public exploit

Unauthenticated data access via hard-coded Telnet credentials

Published Jun 4, 2021 · Updated Aug 4, 2024

Hard-coded credentials in the Telnet service of D-Link DIR-880L 1.07 allow attackers to access the router and read sensitive data. The firmware's etc/init0.d/S80telnetd.sh script launches telnetd with a fixed username and a password read from etc/config/image_sign. Exploitation requires LAN or Wi-Fi adjacency and no prior authentication; successful Telnet login grants router access and exposes stored data.

CVSS severity7.5
High
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

Hard-coded credentials in the Telnet service of D-Link DIR-880L 1.07 allow attackers to access the router and read sensitive data. The firmware's etc/init0.d/S80telnetd.sh script launches telnetd with a fixed username and a password read from etc/config/image_sign. Exploitation requires LAN or Wi-Fi adjacency and no prior authentication; successful Telnet login grants router access and exposes stored data.

The record

CVE
CVE-2020-29322
Published
Jun 4, 2021
Updated
Aug 4, 2024
Vendor
D-Link
Product
DIR-880L
Classifications
CWE-798, CWE-522, T1552.001
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 4, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.07

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

D-Link · DIR-880Lversion=1.07

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N

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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
CWE-522Insufficiently Protected Credentials
T1552.001Credentials In Files

Public exploit references

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Technologies

Your stack

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Your stack

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