CVE-2026-42511: Remote code execution via malicious DHCP options
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.4%
EPSS score, percentile 37.2 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 8.1 High
CVSS v3.1 base score, from CISA's enrichment of the record
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
- Which versions are affected?
Affected
- from 15.0-RELEASE to before p7
- from 14.4-RELEASE to before p3
- from 14.3-RELEASE to before p12
- from 13.5-RELEASE to before p13
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 15.0-RELEASE to before p7 |
| Affected | from 14.4-RELEASE to before p3 |
| Affected | from 14.3-RELEASE to before p12 |
| Affected | from 13.5-RELEASE to before p13 |
Versions not listed are: unknown.
Source: CVE List, as of . About the data.
About this vulnerability
The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives. When the lease file is subsequently re-parsed by dhclient, e.g., after a system restart, an attacker-controlled field from the lease is passed to dhclient-script(8), which evaluates it. A rogue DHCP server may be able to execute arbirary code as ro…
Summary: CVE record, as of .
- CISA has not added CVE-2026-42511 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 30 Apr 2026.
- The CVE record carries a CVSS v3.1 base score of 8.1 (High), taken from CISA's enrichment of the record.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.4% (percentile 37.2), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable no, technical impact total.
- The credits in the CVE record name AISLE as finder.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
Remote code execution via malicious DHCP options
The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives. When the lease file is subsequently re-parsed by dhclient, e.g., after a system restart, an attacker-controlled field from the lease is passed to dhclient-script(8), which evaluates it. A rogue DHCP server may be able to execute arbirary code as root on a system running dhclient.
Source: CVE List, as of . About the data.
Weakness
CWE-149
- CWE-149: Improper Neutralization of Quoting Syntax
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |