How severe is CVE-2026-35520?

CVE-2026-35520 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-35520 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-35520?

CVE-2026-35520 affects Pi-hole Ftldns. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-35520?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-35520 have an EU (EUVD) identifier?

Yes. CVE-2026-35520 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19713.

When was CVE-2026-35520 published?

CVE-2026-35520 was published on 2026-04-07 and last updated on 2026-06-17.

CVE-2026-35520

CVE-2026-35520 is a high-severity vulnerability in Pi-hole Ftldns with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-19713
Weakness: CWE-78
Affected product: Pi-hole Ftldns
Published: 2026-04-07
Last modified: 2026-06-17

Description

FTLDNS (pihole-FTL) provides an interactive API and also generates statistics for Pi-hole's Web interface. From 6.0 to before 6.6, the Pi-hole FTL engine contains a Remote Code Execution (RCE) vulnerability in the DHCP lease time configuration parameter (dhcp.leaseTime). This vulnerability allows an authenticated attacker to inject arbitrary dnsmasq configuration directives through newline characters, ultimately achieving command execution on the underlying system. This vulnerability is fixed in 6.6.

Frequently asked questions

What is CVE-2026-35520?: FTLDNS (pihole-FTL) provides an interactive API and also generates statistics for Pi-hole's Web interface. From 6.0 to before 6.6, the Pi-hole FTL engine contains a Remote Code Execution (RCE) vulnerability in the DHCP lease time configuration parameter (dhcp.leaseTime). This vulnerability allows an authenticated attacker to inject arbitrary dnsmasq configuration directives through newline characters, ultimately achieving command execution on the underlying system. This vulnerability is fixed in 6.6.
How severe is CVE-2026-35520?: CVE-2026-35520 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-35520 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-35520?: CVE-2026-35520 affects Pi-hole Ftldns. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-35520?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-35520 have an EU (EUVD) identifier?: Yes. CVE-2026-35520 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19713.
When was CVE-2026-35520 published?: CVE-2026-35520 was published on 2026-04-07 and last updated on 2026-06-17.

References

https://github.com/pi-hole/FTL/security/advisories/GHSA-fqv2-qhfh-ghcj

Affected products (1)

cpe:2.3:a:pi-hole:ftldns:*:*:*:*:*:*:*:*

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