CVE-2026-123571 Hickory DNS from 0.26.0 before 0.26.2 Panic via TSIG RDATA Decoding
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-123571?
CVE-2026-123571 is a high-severity vulnerability in hickory-dns, published on 8 Nov 2026.
Official description
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.
Weakness: CWE-191
Which versions are affected by CVE-2026-123571?
1 open source package ship an affected version, including hickory-proto.
| Package | Affected | Fixed in |
|---|---|---|
hickory-proto crates.io | From 0.26.0 | 0.26.2 |
How do I fix CVE-2026-123571?
Upgrade hickory-proto to 0.26.2 or later.
Is CVE-2026-123571 being exploited?
There is no known exploitation of CVE-2026-123571 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-123571, GHSA-p8hx-6263-88h9, GHSA-x962-5xwx-fr8x, RUSTSEC-2026-0488, UBUNTU-CVE-2026-123571.