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CVE-2018-5743· NVD / CVE Program· CNA isc

Limiting simultaneous TCP clients was ineffective

By design, BIND is intended to limit the number of TCP clients that can be connected at any given time. The number of allowed connections is a tunable parameter which, if unset, defaults to a conservative value for most servers. Unfortunately, the code which was intended to limit the number of simultaneous connections contained an error which could be exploited to grow the number of simultaneous connections beyond this limit. Versions affected: BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.6, 9.12.0 -> 9.12.4, 9.14.0. BIND 9 Supported Preview Edition versions 9.9.3-S1 -> 9.11.5-S3, and 9.11.5-S5. Versions 9.13.0 -> 9.13.7 of the 9.13 development branch are also affected. Versions prior to BIND 9.9.0 have not been evaluated for vulnerability to CVE-2018-5743.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Oct 9, 2019
Updated
Jun 16, 2026
EPSS
6.5% · 94th percentile
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Report tools

JSON

Action score

32

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
2 / 30 · 6.5%

CNA vs NVD score

NVD
7.5
CNA · isc
7.5
agree

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Affected systems

VendorProduct
f5big-ip local traffic manager
f5big-ip application acceleration manager
f5big-ip advanced firewall manager
f5big-ip analytics
f5big-ip access policy manager
f5big-ip application security manager
f5big-ip edge gateway
f5big-ip fraud protection service
f5big-ip global traffic manager
f5big-ip link controller
f5big-ip webaccelerator
f5big-ip policy enforcement manager

and 5 more

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • f5 big-ip access policy manager11.5.2 and later · up to 11.6.5 inclusive
  • f5 big-ip access policy manager14.0.0 and later · up to 14.1.0 inclusive
  • f5 big-ip access policy manager13.1.0 and later · up to 13.1.1 inclusive
  • f5 big-ip access policy manager12.1.0 and later · up to 12.1.4 inclusive
  • f5 big-ip access policy manager15.0.0
  • f5 big-ip advanced firewall manager11.5.2 and later · up to 11.6.5 inclusive
  • f5 big-ip advanced firewall manager12.1.0 and later · up to 12.1.4 inclusive
  • f5 big-ip advanced firewall manager13.1.0 and later · up to 13.1.1 inclusive
  • f5 big-ip advanced firewall manager14.0.0 and later · up to 14.1.0 inclusive
  • f5 big-ip advanced firewall manager15.0.0
  • f5 big-ip analytics11.5.2 and later · up to 11.6.5 inclusive
  • f5 big-ip analytics12.1.0 and later · up to 12.1.4 inclusive
  • f5 big-ip analytics13.0.0 and later · up to 13.1.1 inclusive
  • f5 big-ip analytics14.0.0 and later · up to 14.1.0 inclusive
  • f5 big-ip analytics15.0.0
  • f5 big-ip application acceleration manager14.0.0 and later · up to 14.1.0 inclusive
  • f5 big-ip application acceleration manager11.5.2 and later · up to 11.6.5 inclusive
  • f5 big-ip application acceleration manager12.1.0 and later · up to 12.1.4 inclusive
  • f5 big-ip application acceleration manager13.0.0 and later · up to 13.1.1 inclusive
  • f5 big-ip application acceleration manager15.0.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (isc). Independent of NVD's CPE analysis and usually ahead of it.

  • ISC BIND 9

    • BIND 9.9.0 -> 9.10.8-P1, 9.11.0 -> 9.11.6, 9.12.0 -> 9.12.4, 9.14.0. BIND 9 Supported Preview Edition versions 9.9.3-S1 -> 9.11.5-S3, and 9.11.5-S5. Versions 9.13.0 -> 9.13.7 of the 9.13 development baffected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.10bindfrom 9.9.0 · before 9.14.1-r09.14.1-r0
Alpine:v3.6bindfrom 9.9.0 · before 9.11.6_p1-r09.11.6_p1-r0
Alpine:v3.8bindfrom 9.9.0 · before 9.12.4_p1-r09.12.4_p1-r0
Debian:12bind9before 1:9.11.5.P4+dfsg-41:9.11.5.P4+dfsg-4
Debian:8bind9before 1:9.9.5.dfsg-9+deb8u181:9.9.5.dfsg-9+deb8u18
Debian:9bind9before 1:9.10.3.dfsg.P4-12.3+deb9u51:9.10.3.dfsg.P4-12.3+deb9u5
openSUSE:Leap 15.0bindbefore 9.11.2-lp151.11.3.19.11.2-lp151.11.3.1
openSUSE:Tumbleweedbindbefore 9.16.20-1.49.16.20-1.4
Red Hat:enterprise_linux:6::clientbindbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-chrootbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-debuginfobefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-develbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-libsbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-sdbbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:6::clientbind-utilsbefore 32:9.8.2-0.68.rc1.el6_10.332:9.8.2-0.68.rc1.el6_10.3
Red Hat:enterprise_linux:7::clientbindbefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-chrootbefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-debuginfobefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-develbefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-libsbefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-libs-litebefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-licensebefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-lite-develbefore 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1
Red Hat:enterprise_linux:7::clientbind-pkcs11before 32:9.9.4-74.el7_6.132:9.9.4-74.el7_6.1

+67

Same product

f5: all records

Other highest-scoring records for the same primary product.

  • CVE-2016-9244A BIG-IP virtual server configured with a Client SSL profile that has the non-default Session Tickets option enabled may leak up to 31 bytes
    52Plan
  • CVE-2016-5745F5 BIG-IP LTM systems 11.x before 11.2.1 HF16, 11.3.x, 11.4.x before 11.4.1 HF11, 11.5.0, 11.5.1 before HF11, 11.5.2, 11.5.3, 11.5.4 before
    40Plan
  • CVE-2019-6609Platform dependent weakness.
    39Monitor
  • CVE-2018-5506In F5 BIG-IP 13.0.0, 12.1.0-12.1.2, 11.6.1, 11.5.1-11.5.5, or 11.2.1 the Apache modules apache_auth_token_mod and mod_auth_f5_auth_token.cpp
    39Monitor
  • CVE-2017-6131In some circumstances, an F5 BIG-IP version 12.0.0 to 12.1.2 and 13.0.0 Azure cloud instance may contain a default administrative password w
    39Monitor
  • CVE-2019-6644Similar to the issue identified in CVE-2018-12120, on versions 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.0.0-13.1.2, and 12.1.0-12.1.4 BIG-IP wil
    37Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
alpine:bind9.14.1-r0 · Alpine:v3.10Package registry (OSV)
debian:bind91:9.11.5.P4+dfsg-4 · Debian:12Package registry (OSV)
opensuse:bind9.11.2-lp151.11.3.1 · openSUSE:Leap 15.0Package registry (OSV)
red hat:bind32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-chroot32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-debuginfo32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-debugsource32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-devel32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-export-libs-debuginfo32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-libs32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-libs-debuginfo32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-libs-lite32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-libs-lite-debuginfo32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-license32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
red hat:bind-lite-devel32:9.11.4-17.P2.el8_0 · Red Hat:enterprise_linux:8::appstreamPackage registry (OSV)
suse:bind9.11.2-12.11.2 · SUSE:Linux Enterprise Module for Basesystem 15Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Noroxi analysis

No Noroxi analysis for this record yet

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Change log

  1. Fix✗ → ✓

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References

All records