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).
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 4.06%
- Percentile among all scored CVEs: 90
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-400
References
- 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
- https://www.debian.org/security/2020/dsa-4689
- https://www.synology.com/security/advisory/Synology_SA_19_39
- 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
- https://www.debian.org/security/2020/dsa-4689
- https://www.synology.com/security/advisory/Synology_SA_19_39
Raw JSON (NVD)
Show
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