CVE-2020-8616 – BIND does not sufficiently limit the number of fetches performed when processing referrals
https://notcve.org/view.php?id=CVE-2020-8616
A malicious actor who intentionally exploits this lack of effective limitation on the number of fetches performed when processing referrals can, through the use of specially crafted referrals, cause a recursing server to issue a very large number of fetches in an attempt to process the referral. This has at least two potential effects: The performance of the recursing server can potentially be degraded by the additional work required to perform these fetches, and The attacker can exploit this behavior to use the recursing server as a reflector in a reflection attack with a high amplification factor. Un actor malicioso que explota intencionalmente esta falta de limitación efectiva en el número de recuperaciones realizadas cuando se procesan referencias puede, mediante el uso de referencias especialmente diseñadas, causar que un servidor recurrente emita una gran cantidad de recuperaciones en un intento de procesar la referencia. Esto tiene al menos dos efectos potenciales: el rendimiento del servidor recurrente puede estar potencialmente afectado por el trabajo adicional requerido para realizar estas recuperaciones, y el atacante puede explotar este comportamiento para utilizar el servidor recurrente como un reflector en un ataque de reflexión con un alto factor de amplificación A flaw was found in BIND, where it does not sufficiently limit the number of fetches that can be performed while processing a referral response. This flaw allows an attacker to cause a denial of service attack. • http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html http://www.nxnsattack.com http://www.openwall.com/lists/oss-security/2020/05/19/4 https://kb.isc.org/docs/cve-2020-8616 https://lists.debian.org/debian-lts-announce/2020/05/msg00031.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JKJXVBOKZ36ER3EUCR7VRB7WGHIIMPNJ https://lists.fedoraproject.org/archi • CWE-400: Uncontrolled Resource Consumption •
CVE-2019-6477 – TCP-pipelined queries can bypass tcp-clients limit
https://notcve.org/view.php?id=CVE-2019-6477
With pipelining enabled each incoming query on a TCP connection requires a similar resource allocation to a query received via UDP or via TCP without pipelining enabled. A client using a TCP-pipelined connection to a server could consume more resources than the server has been provisioned to handle. When a TCP connection with a large number of pipelined queries is closed, the load on the server releasing these multiple resources can cause it to become unresponsive, even for queries that can be answered authoritatively or from cache. (This is most likely to be perceived as an intermittent server problem). Con pipelining habilitada, cada consulta entrante en una conexión TCP requiere una asignación de recursos similar a una consulta recibida por medio de UDP o TCP sin pipelining habilitada. • http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00041.html http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00044.html https://kb.isc.org/docs/cve-2019-6477 https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3DEMNZMKR57VQJCG5ZN55ZGTQRL2TFQ https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XGURMGQHX45KR4QDRCSUQHODUFOGNGAN https://support.f5.com/csp/article/K15840535?utm_source=f5support&%3Butm_medium=RSS http • CWE-400: Uncontrolled Resource Consumption •
CVE-2019-6476 – An error in QNAME minimization code can cause BIND to exit with an assertion failure
https://notcve.org/view.php?id=CVE-2019-6476
A defect in code added to support QNAME minimization can cause named to exit with an assertion failure if a forwarder returns a referral rather than resolving the query. This affects BIND versions 9.14.0 up to 9.14.6, and 9.15.0 up to 9.15.4. Un defecto en el código agregado para soportar la minimización de QNAME puede causar que un nombrado salga con un error de aserción si un reenviador devuelve una referencia en lugar de resolver la consulta. Esto afecta a BIND versiones 9.14.0 hasta 9.14.6 y 9.15.0 hasta 9.15.4. • https://kb.isc.org/docs/cve-2019-6476 https://security.netapp.com/advisory/ntap-20191024-0004 https://support.f5.com/csp/article/K42238532?utm_source=f5support&%3Butm_medium=RSS • CWE-617: Reachable Assertion •
CVE-2019-6475 – A flaw in mirror zone validity checking can allow zone data to be spoofed
https://notcve.org/view.php?id=CVE-2019-6475
Mirror zones are a BIND feature allowing recursive servers to pre-cache zone data provided by other servers. A mirror zone is similar to a zone of type secondary, except that its data is subject to DNSSEC validation before being used in answers, as if it had been looked up via traditional recursion, and when mirror zone data cannot be validated, BIND falls back to using traditional recursion instead of the mirror zone. However, an error in the validity checks for the incoming zone data can allow an on-path attacker to replace zone data that was validated with a configured trust anchor with forged data of the attacker's choosing. The mirror zone feature is most often used to serve a local copy of the root zone. If an attacker was able to insert themselves into the network path between a recursive server using a mirror zone and a root name server, this vulnerability could then be used to cause the recursive server to accept a copy of falsified root zone data. • https://kb.isc.org/docs/cve-2019-6475 https://security.netapp.com/advisory/ntap-20191024-0004 https://support.f5.com/csp/article/K42238532?utm_source=f5support&%3Butm_medium=RSS • CWE-345: Insufficient Verification of Data Authenticity •
CVE-2019-6469 – BIND Supported Preview Edition can exit with an assertion failure if ECS is in use
https://notcve.org/view.php?id=CVE-2019-6469
An error in the EDNS Client Subnet (ECS) feature for recursive resolvers can cause BIND to exit with an assertion failure when processing a response that has malformed RRSIGs. Versions affected: BIND 9.10.5-S1 -> 9.11.6-S1 of BIND 9 Supported Preview Edition. Un error en la funcionalidad EDNS Client Subnet (ECS) para los solucionadores recursivos puede hacer que BIND salga con un fallo de aserción cuando se procesa una respuesta que tiene RRSIG malformados. Versiones afectadas: BIND 9.10.5-S1 hasta 9.11.6-S1 de BIND 9 Supported Preview Edition. • https://kb.isc.org/docs/cve-2019-6469 https://support.f5.com/csp/article/K39751401?utm_source=f5support&%3Butm_medium=RSS • CWE-617: Reachable Assertion •