CVE-2026-27831 json
rldns Vulnerable to Heap-based Out-of-Bounds Read
published 2026-02-26 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-8787
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
rldns is an open source DNS server. Version 1.3 has a heap-based out-of-bounds read that leads to denial of service. Version 1.4 contains a patch for the issue.
Patch / fix
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 8 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/bluedragonsecurity/rldns/security/advisories/GHSA-fv38-45j4-g9x4 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- bluedragonsecurity rldns
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
References
-
github.com
/bluedragonsecurity/rldns/security/advisories/GHSA-fv38-45j4-g9x4
exploit
- github.com /bluedragonsecurity/rldns-1.3-heap-out-of-bounds-vulnerability-fixed-in-rldns-1.4
- github.com /bluedragonsecurity/rldns_archives/blob/main/diff/rldns-1.4.diff
- medium.com /@w1sdom/heap-based-buffer-over-read-vulnerability-in-rldns-1-3-5da3bccdc031
Sources
- CVE List CVE-2026-27831
- NVD CVE-2026-27831
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