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
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 14:02 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/NetworkConfiguration/dhcpcd/co… | patch |
| https://www.vulncheck.com/advisories/dhcpcd-stack… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| NetworkConfiguration | dhcpcd |
Affected:
0 , ≤ 10.3.2
(semver)
Unaffected: 2f00c7bfc408b6582d331932dfa47829c4819029 (git) cpe:2.3:a:dhcpcd_project:dhcpcd:*:*:*:*:*:*:*:* |
Date Public
2026-06-22 00:00
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- 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.
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vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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