CVSS 4.0
8.7 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-123570 hickory-dns hickory-dns: Uncontrolled Resource Consumption
High (8.7) in hickory-dns hickory-dns. EPSS 0.4% estimated probability of exploitation activity in the next 30 days. Fixed in hickory-proto 0.26.2.
On this page
The DNS wire-format message parser in hickory-proto (Hickory DNS) 0.18 before 0.26.2 preallocates record vectors sized by the untrusted ANCOUNT, NSCOUNT, and ARCOUNT header fields before reading record data. Remote attackers can send a UDP datagram, or a spoofed response to a client/resolver, with these counts set to 65535, forcing about 18MB of allocation per message.
Severity
CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- EPSS
- 0.4% estimated probability of exploitation activity in the next 30 days; 36th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: yes · Technical impact: partial, assessed 2026-11-09. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-400 Uncontrolled Resource Consumption
- Published
- Modified
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| hickory-dns | from 0.18 before 0.26.2 |
Fix and patched versions
hickory-proto(crates.io): fixed in 0.26.2- Debian: fixed package versions per release
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| RUSTSEC-2026-0491 | crates.io | hickory-proto | >=0.18.0 <0.26.2 | 0.26.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 13 | rust-hickory-proto | no fix listed | DEBIAN-CVE-2026-123570 |
| Debian | 14 | rust-hickory-proto | 0.26.3-1 | DEBIAN-CVE-2026-123570 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 | rust-hickory-proto | no fix listed | UBUNTU-CVE-2026-123570 |
| Azure Linux | 3 | netavark | no fix listed | AZL-113197 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; Microsoft's Azure Linux vulnerability data, MIT. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
Attack patterns (CAPEC)
- CAPEC-147 XML Ping of the Death Likelihood: Low · Severity: Medium
- CAPEC-227 Sustained Client Engagement
- CAPEC-492 Regular Expression Exponential Blowup
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.