# CVE-2026-14258: Dhcpcd: dhcpcd infinite loop and out-of-bounds read via zero-length ipv6 nd option in router advertisement handling

Status: published. Published: 2026-07-01. Updated: 2026-11-05.

A flaw was found in dhcpcd's IPv6 Neighbor Discovery Router Advertisement processing. A specially crafted IPv6 Router Advertisement containing a zero-length Neighbor Discovery option can bypass validation during packet storage and later be reparsed without adequate validation, causing the parser to enter a non-advancing loop. Successful exploitation may result in excessive CPU consumption, leading to a denial of service.

## Remediation

- workaround: Until an updated package is available, administrators should disable IPv6 Router Advertisement processing on interfaces where it is not required or restrict acceptance of untrusted ICMPv6 Router Advertisements using appropriate network filtering. 

Systems that rely on IPv6 Stateless Address Autoconfiguration (SLAAC) or Router Advertisement-based network configuration should carefully evaluate the operational impact before applying these mitigations. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (dhcpcd): ≥ 0:10.0.6-11.el10_2; < * (unaffected, rpm). Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.40% as of 2026-11-05; percentile 34.06%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-835

## Exploit evidence

- exploit: https://github.com/NetworkConfiguration/dhcpcd/issues/415 (ADP: CISA-ADP)

## References

- https://access.redhat.com/errata/RHSA-2026:54210 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-14258 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2462305 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://github.com/NetworkConfiguration/dhcpcd/commit/75289ca (CNA: redhat)

- https://github.com/NetworkConfiguration/dhcpcd/issues/415 (CNA: redhat)

- https://github.com/NetworkConfiguration/dhcpcd/issues/415 (ADP: CISA-ADP; exploit)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-14258; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-14258; retrieved 2026-11-05; source updated Not reported

Revision: 8fe8367ee31d7a4ea034c847715d241ec9057a94b205a7985aa9b69615a86b36

Canonical: https://y2.dev/cve/CVE-2026-14258

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.