To keep its cache database efficient, `named` running as a recursive resolver occasionally attempts to clean up the…
Summary
Vulnerability reported (CVE-2023-6516). Risk of unauthorized operations or information disclosure. Exploitable via named.
Original description
The description as published by the source.
To keep its cache database efficient, named running as a recursive resolver occasionally attempts to clean up the database. It uses several methods, including some that are asynchronous: a small chunk of memory pointing to the cache element that can be cleaned up is first allocated and then queued for later processing. It was discovered that if the resolver is continuously processing query patterns triggering this type of cache-database maintenance, named may not be able to handle the cleanup events in a timely manner. This in turn enables the list of queued cleanup events to grow infinitely large over time, allowing the configured max-cache-size limit to be significantly exceeded.
This issue affects BIND 9 versions 9.16.0 through 9.16.45 and 9.16.8-S1 through 9.16.45-S1.
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2023-6516 has been found.
Attackers can target a specific entry point like named over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "CVE-2023-6516" on the vendor's site.
CVE-2023-6516
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: named
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) has been reported. Attackers reach the vulnerable code path via named without authentication.
Check the vendor advisory for the affected versions. Attack surface: named.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Alpine Linux ALPINE-CVE-2023-6516 bind Fixed in: 9.16.48-r0
- Debian DEBIAN-CVE-2023-6516 bind9 Fixed in: 1:9.16.48-1
References
- advisory openwall.com
- advisory kb.isc.org
- advisory lists.fedoraproject.org
- advisory lists.fedoraproject.org
- advisory security.netapp.com