Buffer overflow in PowerDNS Recursor before 3.1.7.2 allows remote attackers to cause a denial of service (daemon crash) or possibly execute arbitrary code via crafted packets.
An issue has been found in PowerDNS Recursor versions 4.1.x before 4.1.9 where records in the answer section of responses received from authoritative servers with the AA flag not set were not properly validated, allowing an attacker to bypass DNSSEC validation.
An issue was discovered in PowerDNS Authoritative through 4.3.0 when --enable-experimental-gss-tsig is used. A remote, unauthenticated attacker might be able to cause a double-free, leading to a crash or possibly arbitrary code execution. by sending crafted queries with a GSS-TSIG signature.
dnsdist version 1.1.0 is vulnerable to a flaw in authentication mechanism for REST API potentially allowing CSRF attack.
A vulnerability was found in PowerDNS Authoritative Server before 4.0.7 and before 4.1.7. An insufficient validation of data coming from the user when building a HTTP request from a DNS query in the HTTP Connector of the Remote backend, allowing a remote user to cause a denial of service by making the server connect to an invalid endpoint, or possibly information disclosure by making the server connect to an internal endpoint and somehow extracting meaningful information about the response
An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough privileges to change the system's hostname) to cause disclosure of uninitialized memory content via a stack-based out-of-bounds read. It only occurs on systems where gethostname() does not have '\0' termination of the returned string if the hostname is larger than the supplied buffer. (Linux systems are not affected because the buffer is always large enough. OpenBSD systems are not affected because the returned hostname always has '\0' termination.) Under some conditions, this issue can lead to the writing of one '\0' byte out-of-bounds on the stack, causing a denial of service or possibly arbitrary code execution.
An issue has been found in PowerDNS Recursor versions after 4.1.3 before 4.1.9 where Lua hooks are not properly applied to queries received over TCP in some specific combination of settings, possibly bypassing security policies enforced using Lua.
An issue was discovered in PowerDNS Authoritative through 4.3.0 when --enable-experimental-gss-tsig is used. A remote, unauthenticated attacker can trigger a race condition leading to a crash, or possibly arbitrary code execution, by sending crafted queries with a GSS-TSIG signature.
The label decompression functionality in PowerDNS Recursor before 3.6.4 and 3.7.x before 3.7.3 and Authoritative (Auth) Server before 3.3.3 and 3.4.x before 3.4.5 allows remote attackers to cause a denial of service (CPU consumption or crash) via a request with a long name that refers to itself. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-1868.
An issue has been found in PowerDNS before 3.4.11 and 4.0.2, and PowerDNS recursor before 3.7.4 and 4.0.4, allowing a remote, unauthenticated attacker to cause an abnormal CPU usage load on the PowerDNS server by sending crafted DNS queries, which might result in a partial denial of service if the system becomes overloaded. This issue is based on the fact that the PowerDNS server parses all records present in a query regardless of whether they are needed or even legitimate. A specially crafted query containing a large number of records can be used to take advantage of that behaviour.
Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related RFCs) allow remote attackers to cause a denial of service (CPU consumption) via one or more DNSSEC responses, aka the "KeyTrap" issue. One of the concerns is that, when there is a zone with many DNSKEY and RRSIG records, the protocol specification implies that an algorithm must evaluate all combinations of DNSKEY and RRSIG records.
An attacker can publish a zone containing specific Resource Record Sets. Processing and caching results for these sets can lead to an illegal memory accesses and crash of the Recursor, causing a denial of service.
The remedy is: upgrade to the patched 5.2.1 version.
We would like to thank Volodymyr Ilyin for bringing this issue to our attention.
When DNSdist is configured to provide DoH via the nghttp2 provider, an attacker can cause a denial of service by crafting a DoH exchange that triggers an illegal memory access (double-free) and crash of DNSdist, causing a denial of service.
The remedy is: upgrade to the patched 1.9.9 version.
A workaround is to temporarily switch to the h2o provider until DNSdist has been upgraded to a fixed version.
We would like to thank Charles Howes for bringing this issue to our attention.
In some circumstances, when DNSdist is configured to allow an unlimited number of queries on a single, incoming TCP connection from a client, an attacker can cause a denial of service by crafting a TCP exchange that triggers an exhaustion of the stack and a crash of DNSdist, causing a denial of service.
The remedy is: upgrade to the patched 1.9.10 version.
A workaround is to restrict the maximum number of queries on incoming TCP connections to a safe value, like 50, via the setMaxTCPQueriesPerConnection setting.
We would like to thank Renaud Allard for bringing this issue to our attention.
Unspecified vulnerability in PowerDNS Recursor before 3.1.7.2 allows remote attackers to spoof DNS data via crafted zones.
An issue has been found in PowerDNS Authoritative Server versions up to and including 3.4.10, 4.0.1 allowing an authorized user to crash the server by inserting a specially crafted record in a zone under their control then sending a DNS query for that record. The issue is due to an integer overflow when checking if the content of the record matches the expected size, allowing an attacker to cause a read past the buffer boundary.
An issue has been found in PowerDNS Authoritative Server before 3.4.11 and 4.0.2 allowing a remote, unauthenticated attacker to cause a denial of service by opening a large number of TCP connections to the web server. If the web server runs out of file descriptors, it triggers an exception and terminates the whole PowerDNS process. While it's more complicated for an unauthorized attacker to make the web server run out of file descriptors since its connection will be closed just after being accepted, it might still be possible.
An issue has been found in the parsing of authoritative answers in PowerDNS Recursor before 4.0.8, leading to a NULL pointer dereference when parsing a specially crafted answer containing a CNAME of a different class than IN. An unauthenticated remote attacker could cause a denial of service.
An issue has been found in PowerDNS Recursor before 4.1.18, 4.2.x before 4.2.5, and 4.3.x before 4.3.5. A remote attacker can cause the cached records for a given name to be updated to the Bogus DNSSEC validation state, instead of their actual DNSSEC Secure state, via a DNS ANY query. This results in a denial of service for installation that always validate (dnssec=validate), and for clients requesting validation when on-demand validation is enabled (dnssec=process).
An issue has been found in PowerDNS Recursor 4.1.0 through 4.3.0 where records in the answer section of a NXDOMAIN response lacking an SOA were not properly validated in SyncRes::processAnswer, allowing an attacker to bypass DNSSEC validation.
PowerDNS Recursor from 4.1.0 up to and including 4.3.0 does not sufficiently defend against amplification attacks. An issue in the DNS protocol has been found that allow malicious parties to use recursive DNS services to attack third party authoritative name servers. The attack uses a crafted reply by an authoritative name server to amplify the resulting traffic between the recursive and other authoritative name servers. Both types of service can suffer degraded performance as an effect. This is triggered by random subdomains in the NSDNAME in NS records. PowerDNS Recursor 4.1.16, 4.2.2 and 4.3.1 contain a mitigation to limit the impact of this DNS protocol issue.
PowerDNS Authoritative Server 4.5.0 before 4.5.1 allows anybody to crash the process by sending a specific query (QTYPE 65535) that causes an out-of-bounds exception.
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.
The DNS packet parsing/generation code in PowerDNS (aka pdns) Authoritative Server 3.4.x before 3.4.6 allows remote attackers to cause a denial of service (crash) via crafted query packets.
PowerDNS (aka pdns) Authoritative Server before 3.4.10 allows remote attackers to cause a denial of service (backend CPU consumption) via a long qname.
PowerDNS (aka pdns) Authoritative Server before 3.4.10 does not properly handle a . (dot) inside labels, which allows remote attackers to cause a denial of service (backend CPU consumption) via a crafted DNS query.
An issue has been found in dnsdist before 1.2.0 in the way EDNS0 OPT records are handled when parsing responses from a backend. When dnsdist is configured to add EDNS Client Subnet to a query, the response may contain an EDNS0 OPT record that has to be removed before forwarding the response to the initial client. On a 32-bit system, the pointer arithmetic used when parsing the received response to remove that record might trigger an undefined behavior leading to a crash.
An issue was discovered in PowerDNS Authoritative through 4.3.0 when --enable-experimental-gss-tsig is used. A remote, unauthenticated attacker can cause a denial of service by sending crafted queries with a GSS-TSIG signature.
A vulnerability has been found in PowerDNS Authoritative Server before versions 4.1.10, 4.0.8 allowing an authorized user to cause the server to exit by inserting a crafted record in a MASTER type zone under their control. The issue is due to the fact that the Authoritative Server will exit when it runs into a parsing error while looking up the NS/A/AAAA records it is about to use for an outgoing notify.
Last updated 14 January 2025