CVE-2021-25215
No exploitation reported by the sources we read.
- Published2021-04-29
- Fixed in9.17.12 · 9.16.15 · 9.11.31
- WeaknessCWE-617
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.
Timeline
dates in UTC- 2021-04-2901:15CVE publishedNVD
- 2026-10-2319:23EPSS crossed 10 %FIRST EPSS
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-25215?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-25215?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 9.17 | ≥ 9.17.0, < 9.17.12 | 9.17.12 | NVD |
| 9.x | ≥ 9.12.0, < 9.16.15 | 9.16.15 | NVD |
| 9.x | ≥ 9.0.0, < 9.11.31 | 9.11.31 | NVD |
| 9.9 | = 9.9.3 | no fix published | NVD |
| 9.9 | = 9.9.12 | no fix published | NVD |
| 9.9 | = 9.9.13 | no fix published | NVD |
| 9.10 | = 9.10.5 | no fix published | NVD |
| 9.10 | = 9.10.7 | no fix published | NVD |
| 9.11 | = 9.11.3 | no fix published | NVD |
| 9.11 | = 9.11.5 | no fix published | NVD |
| 9.11 | = 9.11.6 | no fix published | NVD |
| 9.11 | = 9.11.7 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 9.0 | = 9.0 | no fix published | NVD |
| 10.0 | = 10.0 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 33.x | = 33 | no fix published | NVD |
| 34.x | = 34 | no fix published | NVD |
13 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Isc bind to 9.17.12 · 9.16.15 · 9.11.31
Advisories and patches
- cert-portal.siemens.comPatch
- kb.isc.orgVendor Advisory
- www.oracle.comPatch
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- CNACVSS 3.17.5read 2026-10-23
- NVDCVSS 3.17.5read 2026-10-23
- NVDCVSS 2.05read 2026-10-23
- NVDweakness (CWE)CWE-617read 2026-10-23
- FIRST EPSSEPSS score11.8 %read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2021-04-29
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-25215?
Is CVE-2021-25215 actively exploited?
What is the CVSS score for CVE-2021-25215?
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Related vulnerabilities
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