CVE-2026-123571 json
Hickory DNS from 0.26.0 before 0.26.2 Panic via TSIG RDATA Decoding
published 2mo ago modified 53m ago also EUVD-2026-119456 , GHSA-x962-5xwx-fr8x , RUSTSEC-2026-0488
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 35%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- crates.io hickory-proto 0.26.2
- hickory-dns hickory-dns 0.26.2
- rust-hickory-dns Debian 14 0.26.3-1
debian advisories DEBIAN-CVE-2026-123571
Is CVE-2026-123571 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | hickory-proto | >=0.26.0, <0.26.2 |
0.26.2 |
Affected products
- hickory-dns hickory-dns
Classification
- Weakness
-
- CWE-191 Integer Underflow (Wrap or Wraparound)
References
-
github.com
/hickory-dns/hickory-dns/commit/b1246a8a21b6dcc34d427a7d39dd96e10825c384
web
-
github.com
/hickory-dns/hickory-dns/security/advisories/GHSA-x962-5xwx-fr8x
vendor-advisory, advisory
-
vulncheck.com
/advisories/hickory-dns-from-0.26.0-before-0.26.2-panic-via-tsig-rdata-decoding
third-party-advisory
-
crates.io
/crates/hickory-proto
package
-
rustsec.org
/advisories/RUSTSEC-2026-0488.html
advisory
Sources
- CVE List CVE-2026-123571
- NVD CVE-2026-123571
- OSV RUSTSEC-2026-0488
- Maintainer advisory GHSA-x962-5xwx-fr8x
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of hickory-dns/hickory-dns published their own advisory on GitHub. Reviewed sources take precedence over it.