CVE-2022-39028Public exploitNetwork attack vector

Service interruption via uninitialized SLC pointer dereference

Published Aug 30, 2022 · Updated Aug 3, 2024

NULL pointer dereference in GNU Inetutils telnetd 2.3 and earlier allows remote attackers to crash the server with a two-byte command. The telrcv routine in telnetd/state.c processes IAC EC or IAC EL before the SLC table is initialized, then dereferences a null sptr entry; MIT krb5-appl 1.0.3 and earlier shares the code. No authentication is required, and repeated requests can trigger inetd's looping-failure limit and terminate the telnet service.

CVSS severity7.5
High
EPSS probability2.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in GNU Inetutils telnetd 2.3 and earlier allows remote attackers to crash the server with a two-byte command. The telrcv routine in telnetd/state.c processes IAC EC or IAC EL before the SLC table is initialized, then dereferences a null sptr entry; MIT krb5-appl 1.0.3 and earlier shares the code. No authentication is required, and repeated requests can trigger inetd's looping-failure limit and terminate the telnet service.

The record

CVE
CVE-2022-39028
Published
Aug 30, 2022
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-476, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 30, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5SUSECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499Endpoint Denial of Service

Public exploit references

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Technologies

Your stack

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Your stack

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