CVE-2018-16855
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending...
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
CVE-2018-16855- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2018-8648
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
EUVD-2018-8648- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qx96-6995-fgrp
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending...
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
GHSA-qx96-6995-fgrp- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-125
- Updated
- 2026-11-02
NVD
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
CVE-2018-16855- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-125
- Updated
- 2026-11-02
OSV
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
CVE-2018-16855- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-16855
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
DEBIAN-CVE-2018-16855- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 5 moreShow less
OSVUBUNTU-CVE-2018-16855
7.5
An issue has been found in PowerDNS Recursor before version 4.1.8 where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash.
- Record
UBUNTU-CVE-2018-16855- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVMGASA-2019-0009 No score
Updated pdns-recursor packages fix security vulnerabilities
A vulnerability was in found in PowerDNS Recursor. The issue is a memory leak occurring while parsing some malformed records, due to the fact that some memory is allocated parsing a record and is not always properly released if the record is not valid. It allows a malicious auth server to cause a denial of service by sending specially crafted records in response to a legitimate query by an authorized user (CVE-2018-10851).
An issue has been found in PowerDNS Recursor allowing a remote user to craft a DNS query that will cause an answer without DNSSEC records to be inserted into the packet cache and be returned to clients asking for DNSSEC records, thus hiding the presence of DNSSEC signatures for a specific qname and qtype. For a DNSSEC-signed domain, this means that clients performing DNSSEC validation by themselves might consider the answer to be bogus until it expires from the packet cache, leading to a denial of service (CVE-2018-14626).
An issue has been found in PowerDNS Recursor from 4.0.0 up to and including 4.1.4. A remote attacker sending a DNS query for a meta-type like OPT can lead to a zone being wrongly cached as failing DNSSEC validation. It only arises if the parent zone is signed, and all the authoritative servers for that parent zone answer with FORMERR to a query for at least one of the meta-types. As a result, subsequent queries from clients requesting DNSSEC validation will be answered with a ServFail (CVE-2018-14644).
An issue has been found in PowerDNS Recursor where a remote attacker sending a DNS query can trigger an out-of-bounds memory read while computing the hash of the query for a packet cache lookup, possibly leading to a crash (CVE-2018-16855).
- Record
MGASA-2019-0009- Updated
- 2026-11-02
OSVopenSUSE-SU-2018:4062-1 No score
Security update for pdns-recursor
This update for pdns-recursor to version 4.1.8 fixes the following issues:
Security issues fixed:
- CVE-2018-10851: Fixed denial of service via crafted zone record or crafted answer (bsc#1114157).
- CVE-2018-14644: Fixed denial of service via crafted query for meta-types (bsc#1114170).
- CVE-2018-14626: Fixed packet cache pollution via crafted query (bsc#1114169).
- CVE-2018-16855: Fixed case where a crafted query could cause a denial of service (bsc#1116592)
Non-security issues fixed:
- Fixed build failure with Boost 1.67.0 (bsc#1089814).
- Revert ‘Keep the EDNS status of a server on FormErr with EDNS’
- Refuse queries for all meta-types
For more details about this update, refer to: https://blog.powerdns.com/2018/11/26/powerdns-recursor-4-1-8-released/
- Record
openSUSE-SU-2018:4062-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2018:4177-1 No score
Security update for pdns-recursor
This update for pdns-recursor fixes the following issues:
Security issues fixed:
- CVE-2018-10851: Fixed denial of service via crafted zone record or crafted answer (bsc#1114157).
- CVE-2018-14644: Fixed denial of service via crafted query for meta-types (bsc#1114170).
- CVE-2018-14626: Fixed packet cache pollution via crafted query (bsc#1114169).
- CVE-2018-16855: Fixed case where a crafted query could cause a denial of service (bsc#1116592)
This update was imported from the openSUSE:Leap:15.0:Update update project.
- Record
openSUSE-SU-2018:4177-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:11157-1 No score
pdns-recursor-4.5.5-1.3 on GA media
These are all security issues fixed in the pdns-recursor-4.5.5-1.3 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:11157-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
pdns-recursorDebian:12 |
before 4.1.8-1 | 4.1.8-1 |
pdns-recursorDebian:13 |
before 4.1.8-1 | 4.1.8-1 |
pdns-recursorDebian:14 |
before 4.1.8-1 | 4.1.8-1 |
pdns-recursorMageia:6 From an advisory covering 4 CVEs |
before 4.1.8-1.mga6 | 4.1.8-1.mga6 |
pdns-recursorUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 4.0.6-14.0.6-1build14.0.7-14.1.1-14.1.1-1build14.1.1-24.1.1-2ubuntu0.1~esm1 |
None known |
pdns-recursorSUSE:Package Hub 12 SP1 From an advisory covering 4 CVEs |
before 4.1.8-13.1 | 4.1.8-13.1 |
pdns-recursorSUSE:Package Hub 15 From an advisory covering 4 CVEs |
before 4.1.2-bp150.2.3.1 | 4.1.2-bp150.2.3.1 |
pdns-recursoropenSUSE:Tumbleweed From an advisory covering 18 CVEs |
before 4.5.5-1.3 | 4.5.5-1.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases, products | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-16855 is a high vulnerability (CVSS 7.5) in Powerdns Recursor, published December 3, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 58.6%, the 99th percentile. Fixed in pdns-recursor 4.1.8-1.
References
bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16855
docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2018-09.html
nvd.nist.gov/vuln/detail/CVE-2018-16855
github.com/advisories/GHSA-qx96-6995-fgrp
security-tracker.debian.org/tracker/CVE-2018-16855
advisories.mageia.org/MGASA-2019-0009.html
Show 33 moreShow less
bugs.mageia.org/show_bug.cgi?id=23815
doc.powerdns.com/recursor/security-advisories/powerdns-advisory-2018-04.html
doc.powerdns.com/recursor/security-advisories/powerdns-advisory-2018-06.html
docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2018-07.html
lists.fedoraproject.org/archives/list/[email protected]/thread/U5BJ2CLRPCLSDHOH3VAABZZP4GVKGLL5
ubuntu.com/security/CVE-2018-16855
doc.powerdns.com/recursor/security-advisories/powerdns-advisory-2018-09.html
cve.org/CVERecord?id=CVE-2018-16855
lists.opensuse.org/archives/list/[email protected]/thread/FI4FFU4QQEWV74MZWYUFSQ5ZMXRGIH7G
bugzilla.suse.com/1089814
bugzilla.suse.com/1114157
bugzilla.suse.com/1114169
bugzilla.suse.com/1114170
bugzilla.suse.com/1116592
suse.com/security/cve/CVE-2018-10851
suse.com/security/cve/CVE-2018-14626
suse.com/security/cve/CVE-2018-14644
suse.com/security/cve/CVE-2018-16855
lists.opensuse.org/archives/list/[email protected]/thread/M2UYXXO7I4TUSSSVHBOZEQKRR4SWMVXY
suse.com/security/cve/CVE-2016-2120
suse.com/security/cve/CVE-2016-7068
suse.com/security/cve/CVE-2017-15090
suse.com/security/cve/CVE-2017-15092
suse.com/security/cve/CVE-2017-15093
suse.com/security/cve/CVE-2017-15094
suse.com/security/cve/CVE-2018-1000003
suse.com/security/cve/CVE-2019-3806
suse.com/security/cve/CVE-2019-3807
suse.com/security/cve/CVE-2020-10030
suse.com/security/cve/CVE-2020-10995
suse.com/security/cve/CVE-2020-12244
suse.com/security/cve/CVE-2020-14196
suse.com/security/cve/CVE-2020-25829