CVE Intelligence
High Denial of service

CVE-2023-2828 — named's configured cache size limit can be significantly exceeded

Every `named` instance configured to run as a recursive resolver maintains a cache database holding the responses to the queries it has recently sent to authoritative servers. The size limit for that cache database can be configured using the `max-cache-size` statement in the configuration file; it defaults to 90% of the total amount of memory available on the host. When the size of the cache reaches 7/8 of the configured limit, a cache-cleaning algorithm starts to remove expired and/or least-recently used RRsets from the cache, to keep memory use below the configured limit. It has been discovered that the effectiveness of the cache-cleaning algorithm used in `named` can be severely diminished by querying the resolver for specific RRsets in a certain order, effectively allowing the configured `max-cache-size` limit to be significantly exceeded. This issue affects BIND 9 versions 9.11.0 through 9.16.41, 9.18.0 through 9.18.15, 9.19.0 through 9.19.13, 9.11.3-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1.

Published Jun 21, 2023 · Updated Oct 24, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: isc

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 3.7% (30-day exploitation probability)+13
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
3.7%
ahead of 90% of scored CVEs · Oct 29, 2026
Affects
Debian
Debian Linux and 9 more
CVSS base
7.5
High · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Fedoraproject Fedora, Isc Bind…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Search available logs for exploit probes matching the vulnerability class (denial of service), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Debian Debian Linux version 10.0version 11.0version 12.0 Vulnerable NIST National Vulnerability Database
Fedoraproject Fedora version 38version 37 Vulnerable NIST National Vulnerability Database
Isc Bind ≥ 9.11.0 and ≤ 9.16.41≥ 9.11.3 and ≤ 9.16.41≥ 9.18.0 and ≤ 9.18.15≥ 9.18.11 and ≤ 9.18.15≥ 9.19.0 and ≤ 9.19.13 Vulnerable NIST National Vulnerability Database
ISC BIND 9 ≥ 9.18.11-S1 and ≤ 9.18.15-S1≥ 9.11.3-S1 and ≤ 9.16.41-S1≥ 9.19.0 and ≤ 9.19.13≥ 9.18.0 and ≤ 9.18.15≥ 9.11.0 and ≤ 9.16.41 Vulnerable CVE Program (cve.org) e CISA ADP
Netapp Active Iq Unified Manager versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp H300s Firmware versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp H410c Firmware versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp H410s Firmware versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp H500s Firmware versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp H700s Firmware versions not specified by the source Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.5 CVSS 3.1 High 3.9 3.6 security-officer@isc.org via NIST National Vulnerability Database
7.5 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
7.5 CVSS 3.1 High — — isc via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: security-officer@isc.org)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-770 · Allocation of Resources Without Limits or Throttling

Other CVEs with this weakness →

EPSS over time FIRST

Oct 24, 2026 → Oct 29, 2026 · 6 reading(s) · max 3.70%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Track CPU/memory spikes and availability drops correlated with request patterns.
web/proxy/WAF logsnetwork IDS/IPSresource metrics

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · isc/bind 9
    Oct 24, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 24, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 24, 2026
  • Fix documented
    Oct 24, 2026 · NIST National Vulnerability Database
  • Affected products added · isc/bind, debian/debian linux, fedoraproject/fedora, netapp/active iq unified manager, netapp/h500s firmware, netapp/h70
    Oct 24, 2026 · NIST National Vulnerability Database
  • CVSS changed · 7.5
    Oct 24, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 24, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 24, 2026 · Alertas do Telegram
  • 2023
  • CVE published
    Jun 21, 2023 · isc

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 24, 2026 – Oct 24, 2026
  • 1× Official description updated · Oct 24, 2026 – Oct 24, 2026

References

12 on the record

Elsewhere on this site

Debian
every CVE for this vendor
CWE-770
other pages naming this weakness

Related CVEs (same products)

  • Critical CVE-2026-111497 Google Brotli Unchecked Return Value Vulnerability KEV 8d
  • High CVE-2026-97313 Specific RPZ configurations and query patterns may result in an unexpected exit 9d
  • High CVE-2026-94300 Concurrent GSS-TSIG messages corrupt memory 9d
  • High CVE-2026-96888 Named may terminate unexpectedly when a redirect zone is used with strict QNAME minimization 9d
  • High CVE-2026-19630 Amplified resource exhaustion in inbound message processing 9d
  • High CVE-2026-80274 Validating resolver can abort while caching a mismatched NOQNAME proof Sep 16, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-2828 is "named's configured cache size limit can be significantly exceeded", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 3.70% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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