CVE-2023-37459Network attack vector

Packet-buffer over-read via truncated TCP SYN header

Published Sep 15, 2023 · Updated Sep 25, 2024

Out-of-bounds read in Contiki-NG 4.9 and earlier allows remote attackers to read beyond packet data via a truncated TCP SYN packet. The check_for_tcp_syn function reads UIP_TCP_BUF->flags before confirming that the received packet contains a complete TCP header. The malformed packet requires no authentication or user interaction; the advisory reports neither a write nor a remote data-return or service-interruption path.

CVSS severity5.3
Medium
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Contiki-NG 4.9 and earlier allows remote attackers to read beyond packet data via a truncated TCP SYN packet. The check_for_tcp_syn function reads UIP_TCP_BUF->flags before confirming that the received packet contains a complete TCP header. The malformed packet requires no authentication or user interaction; the advisory reports neither a write nor a remote data-return or service-interruption path.

The record

CVE
CVE-2023-37459
Published
Sep 15, 2023
Updated
Sep 25, 2024
Vendor
Contiki-NG
Product
Contiki-NG
Classifications
CWE-125
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 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=<= 4.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Contiki-NG · Contiki-NGversion=<= 4.9

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read

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.

Technologies

Your stack

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Your stack

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