CVE-2026-52688: RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation

highCVSS 7.5CVE-2026-52688

RRSIGs with too few labels can lead to bypass of DNSSEC wildcard validation

Details

Source: NVD Recent CVEs (US · database · site)
Severity: high — CVSS 7.5
Published: 2026-07-23
Last updated: 2026-07-23
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-52688

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-526880.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-52688	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[NEW] [medium] PowerDNS: Multiple Vulnerabilities Allow Bypassing of Security Measurescert-bund
unknownDSA-6397-1 pdns-recursor - security updatedebian

Recent advisories for RRSIGs with too

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-13204: If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and t…nvd · 2026-07-22
highCVE-2026-11721: It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller n…nvd · 2026-07-22
highCVE-2026-11605: The issue is a resource exhaustion vulnerability associated with DNSSEC validation. BIND alway…nvd · 2026-07-22
mediumCVE-2026-56416: In NLnet Labs Unbound up to and including version 1.25.1, when the validator builds the canoni…nvd · 2026-07-22
lowCVE-2026-46582: In NLnet Labs Unbound 1.6.0 up to and including 1.25.1, a replay of a wildcard rrset as anothe…nvd · 2026-07-22
highCVE-2026-11721: Cache poisoning possible with label count discrepancy, RRSIG, and wildcardsmsrc · 2026-07-14