CVE-2018-5734 | A malformed request can trigger an assertion failure in badcache.c

While handling a particular type of malformed packet BIND erroneously selects a SERVFAIL rcode instead of a FORMERR rcode. If the receiving view has the SERVFAIL cache feature enabled, this can trigger an assertion failure in badcache.c when the request doesn't contain all of the expected information. Affects BIND 9.10.5-S1 to 9.10.5-S4, 9.10.6-S1, 9.10.6-S2.

Published: 2019-01-16 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-5734 is rated High Risk (66.3/100): CVSS High severity, with high exploitation likelihood (EPSS 8.55%, 94th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +3.31% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-5734

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 5.24% 8.55% +3.31%
2 2026-04-15 6.40% 5.24% -1.16%
3 2026-02-03 — 6.40% —

Full EPSS history (17 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-5734

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2018-5734

OS Trackers for CVE-2018-5734

vendor priority summary link
debian unimportant CVE-2018-5734 unimportant priority: Debian including 1 source packages (bind9), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2018-5734
redhat high — https://access.redhat.com/security/cve/CVE-2018-5734
ubuntu medium CVE-2018-5734 medium priority: Ubuntu including 1 source packages (bind9), 4 status rows across 4 suites (artful, trusty, upstream, xenial): not-affected 3, needs-triage 1. https://ubuntu.com/security/CVE-2018-5734

Affected software / configurations for CVE-2018-5734

Vendor Product Version Raw CPE
isc bind 9.10.5 cpe:2.3:a:isc:bind:9.10.5:s1:*:*:*:*:*:*
isc bind 9.10.5 cpe:2.3:a:isc:bind:9.10.5:s4:*:*:*:*:*:*
isc bind 9.10.6 cpe:2.3:a:isc:bind:9.10.6:s1:*:*:*:*:*:*
isc bind 9.10.6 cpe:2.3:a:isc:bind:9.10.6:s2:*:*:*:*:*:*
netapp data_ontap_edge — cpe:2.3:a:netapp:data_ontap_edge:-:*:*:*:*:*:*:*
netapp solidfire_element_os_management_node — cpe:2.3:a:netapp:solidfire_element_os_management_node:-:*:*:*:*:*:*:*

References for CVE-2018-5734

URL Tags
http://www.securityfocus.com/bid/103189 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1040438 Third Party Advisory VDB Entry
https://kb.isc.org/docs/aa-01562 Vendor Advisory
https://security.netapp.com/advisory/ntap-20180926-0005/ Third Party Advisory
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