CVE-2026-27853
CVE-2026-27853 is a medium-severity vulnerability in Powerdns Dnsdist with a CVSS 3.x base score of 5.9. 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-787.
Key facts
- Severity: Medium (CVSS 3.x base score 5.9)
- EPSS exploit prediction: 0% (39th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-17407
- Weakness: CWE-787
- Affected product: Powerdns Dnsdist
- Published:
- Last modified:
Description
An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.
Frequently asked questions
- What is CVE-2026-27853?
- An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.
- How severe is CVE-2026-27853?
- CVE-2026-27853 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2026-27853 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-27853?
- CVE-2026-27853 affects Powerdns Dnsdist. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-27853?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-27853 have an EU (EUVD) identifier?
- Yes. CVE-2026-27853 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17407.
- When was CVE-2026-27853 published?
- CVE-2026-27853 was published on 2026-03-31 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:*
More vulnerabilities in Powerdns Dnsdist
- CVE-2017-7557 — High (CVSS 8.8): dnsdist version 1.1.0 is vulnerable to a flaw in authentication mechanism for REST API potentially allowing CSRF attack.
- CVE-2026-33593 — High (CVSS 7.5): A client can trigger a divide by zero error leading to crash by sending a crafted DNSCrypt query.
- CVE-2026-33602 — Medium (CVSS 6.5): A rogue backend can send a crafted UDP response with a query ID off by one related to the maximum configured value,…
- CVE-2026-24029 — Medium (CVSS 6.5): When the early_acl_drop (earlyACLDrop in Lua) option is disabled (default is enabled) on a DNS over HTTPs frontend…
- CVE-2018-14663 — Medium (CVSS 5.9): An issue has been found in PowerDNS DNSDist before 1.3.3 allowing a remote attacker to craft a DNS query with trailing…
- CVE-2016-7069 — Medium (CVSS 5.9): An issue has been found in dnsdist before 1.2.0 in the way EDNS0 OPT records are handled when parsing responses from a…
All CVEs affecting Powerdns Dnsdist →
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