CVE-2023-4236

named may terminate unexpectedly under high DNS-over-TLS query load

HIGH
7.5
CVSS Score
Published: September 20, 2023 at 12:32 PM UTC
Updated: June 17, 2026 at 06:37 AM UTC
13 products affected across 4 vendorsDebian LinuxFedoraH700S Firmware

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Severity
HIGH7.5
Exploit prediction
EPSS 2%

Description

A flaw in the networking code handling DNS-over-TLS queries may cause `named` to terminate unexpectedly due to an assertion failure. This happens when internal data structures are incorrectly reused under significant DNS-over-TLS query load. This issue affects BIND 9 versions 9.18.0 through 9.18.18 and 9.18.11-S1 through 9.18.18-S1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

9.18.0 ≤ v ≤ 9.18.189.18.0 ≤ v < 9.18.189.18.11-S1 ≤ v ≤ 9.18.18-S19.18.09.18.11 s19.18.11-S19.18.18 s1
Affected range stops below 9.18.18, so it looks safe — our inference, not a vendor statement
All versions
netapp-h300s (same device)
All versions
netapp-h410c (same device)
All versions
netapp-h410s (same device)
All versions
netapp-h500s (same device)
All versions
netapp-h700s (same device)
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

CVSS

7.5HIGHisc
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-617

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