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-2026-123571 Hickory DNS from 0.26.0 before 0.26.2 Panic via TSIG RDATA Decoding
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
Hickory DNS from 0.26.0 before 0.26.2 contains an integer underflow vulnerability in TSIG RDATA decoding that allows remote attackers to trigger a panic via malformed records. Attackers can send a crafted TSIG record in DNS wire format to cause unchecked subtraction underflow, crashing builds with overflow checks enabled and causing denial of service.
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 2026-11-13. 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-191 Integer Underflow (Wrap or Wraparound)
- Published
- Modified
- Assigned by
- VulnCheck (CNA)
- 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 0.26.0 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-2026-0488 | crates.io | hickory-proto | >=0.26.0 <0.26.2 | 0.26.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 13 | rust-hickory-dns | no fix listed | DEBIAN-CVE-2026-123571 |
| Debian | 14 | rust-hickory-dns | 0.26.3-1 | DEBIAN-CVE-2026-123571 |
| Ubuntu | 26.04:LTS, 26.10 | rust-hickory-dns | no fix listed | UBUNTU-CVE-2026-123571 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu.
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.