CVE-2026-56114 (GCVE-0-2026-56114)

Vulnerability from cvelistv5 – Published: 2026-06-23 16:08 – Updated: 2026-07-28 01:49 X_Open Source
VLAI
Title
dhcpcd Stack Out-of-Bounds Write in dhcp6_makemessage()
Summary
dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.
Severity
6 (Medium)
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 14:02 UTC
CWE
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6518 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NetworkConfiguration dhcpcd Affected: 0 , ≤ 10.3.2 (semver)
Unaffected: 2f00c7bfc408b6582d331932dfa47829c4819029 (git)
    cpe:2.3:a:dhcpcd_project:dhcpcd:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-22 00:00
Credits
CuB3y0nd VulnCheck
Show details on NVD website
To clipboard 

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  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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