{"document":{"aggregate_severity":{"namespace":"https://www.suse.com/support/security/rating/","text":"moderate"},"category":"csaf_vex","csaf_version":"2.0","distribution":{"text":"Copyright 2024 SUSE LLC. All rights reserved.","tlp":{"label":"WHITE","url":"https://www.first.org/tlp/"}},"lang":"en","notes":[{"category":"summary","text":"SUSE CVE-2025-47950","title":"Title"},{"category":"description","text":"CoreDNS is a DNS server that chains plugins. In versions prior to 1.12.2, a Denial of Service (DoS) vulnerability exists in the CoreDNS DNS-over-QUIC (DoQ) server implementation. The server previously created a new goroutine for every incoming QUIC stream without imposing any limits on the number of concurrent streams or goroutines. A remote, unauthenticated attacker could open a large number of streams, leading to uncontrolled memory consumption and eventually causing an Out Of Memory (OOM) crash - especially in containerized or memory-constrained environments. The patch in version 1.12.2 introduces two key mitigation mechanisms: `max_streams`, which caps the number of concurrent QUIC streams per connection with a default value of `256`; and `worker_pool_size`, which Introduces a server-wide, bounded worker pool to process incoming streams with a default value of `1024`. This eliminates the 1:1 stream-to-goroutine model and ensures that CoreDNS remains resilient under high concurrency.  Some workarounds are available for those who are unable to upgrade. Disable QUIC support by removing or commenting out the `quic://` block in the Corefile, use container runtime resource limits to detect and isolate excessive memory usage, and/or monitor QUIC connection patterns and alert on anomalies.","title":"Description of the CVE"},{"category":"legal_disclaimer","text":"CSAF 2.0 data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0).","title":"Terms of use"}],"publisher":{"category":"vendor","contact_details":"https://www.suse.com/support/security/contact/","name":"SUSE Product Security Team","namespace":"https://www.suse.com/"},"references":[{"category":"external","summary":"CVE-2025-47950","url":"https://www.suse.com/security/cve/CVE-2025-47950"},{"category":"external","summary":"SUSE Security Ratings","url":"https://www.suse.com/support/security/rating/"},{"category":"external","summary":"SUSE Bug 1244331 for CVE-2025-47950","url":"https://bugzilla.suse.com/1244331"}],"title":"SUSE CVE CVE-2025-47950","tracking":{"current_release_date":"2026-01-31T00:27:32Z","generator":{"date":"2025-08-25T23:22:47Z","engine":{"name":"cve-database.git:bin/generate-csaf-vex.pl","version":"1"}},"id":"CVE-2025-47950","initial_release_date":"2025-08-25T23:22:47Z","revision_history":[{"date":"2025-08-25T23:22:47Z","number":"2","summary":"Current version"},{"date":"2025-11-02T03:54:53Z","number":"3","summary":"Current version"},{"date":"2025-12-17T00:29:12Z","number":"4","summary":"description changed"},{"date":"2025-12-19T00:29:04Z","number":"5","summary":"description changed"},{"date":"2026-01-31T00:27:32Z","number":"6","summary":"unknown changes"}],"status":"interim","version":"6"}},"product_tree":{"branches":[{"branches":[{"branches":[{"category":"product_name","name":"SUSE Linux Enterprise Server 16.0","product":{"name":"SUSE Linux Enterprise Server 16.0","product_id":"SUSE Linux Enterprise Server 16.0","product_identification_helper":{"cpe":"cpe:/o:suse:sles:16:16.0:server"}}},{"category":"product_name","name":"openSUSE Tumbleweed","product":{"name":"openSUSE Tumbleweed","product_id":"openSUSE Tumbleweed","product_identification_helper":{"cpe":"cpe:/o:opensuse:tumbleweed"}}},{"category":"product_version","name":"govulncheck-vulndb-0.0.20250612T141001-1.1","product":{"name":"govulncheck-vulndb-0.0.20250612T141001-1.1","product_id":"govulncheck-vulndb-0.0.20250612T141001-1.1","product_identification_helper":{"purl":"pkg:rpm/suse/govulncheck-vulndb@0.0.20250612T141001-1.1?upstream=govulncheck-vulndb-0.0.20250612T141001-1.1.src.rpm"}}},{"category":"product_version","name":"govulncheck-vulndb-0.0.20250814T182633-160000.1.2","product":{"name":"govulncheck-vulndb-0.0.20250814T182633-160000.1.2","product_id":"govulncheck-vulndb-0.0.20250814T182633-160000.1.2","product_identification_helper":{"purl":"pkg:rpm/suse/govulncheck-vulndb@0.0.20250814T182633-160000.1.2?upstream=govulncheck-vulndb-0.0.20250814T182633-160000.1.2.src.rpm"}}}],"category":"product_family","name":"SUSE Linux Enterprise"}],"category":"vendor","name":"SUSE"}],"relationships":[{"category":"default_component_of","full_product_name":{"name":"govulncheck-vulndb-0.0.20250814T182633-160000.1.2 as component of SUSE Linux Enterprise Server 16.0","product_id":"SUSE Linux Enterprise Server 16.0:govulncheck-vulndb-0.0.20250814T182633-160000.1.2"},"product_reference":"govulncheck-vulndb-0.0.20250814T182633-160000.1.2","relates_to_product_reference":"SUSE Linux Enterprise Server 16.0"},{"category":"default_component_of","full_product_name":{"name":"govulncheck-vulndb-0.0.20250612T141001-1.1 as component of openSUSE Tumbleweed","product_id":"openSUSE Tumbleweed:govulncheck-vulndb-0.0.20250612T141001-1.1"},"product_reference":"govulncheck-vulndb-0.0.20250612T141001-1.1","relates_to_product_reference":"openSUSE Tumbleweed"}]},"vulnerabilities":[{"cve":"CVE-2025-47950","ids":[{"system_name":"SUSE CVE Page","text":"https://www.suse.com/security/cve/CVE-2025-47950"}],"notes":[{"category":"general","text":"CoreDNS is a DNS server that chains plugins. In versions prior to 1.12.2, a Denial of Service (DoS) vulnerability exists in the CoreDNS DNS-over-QUIC (DoQ) server implementation. The server previously created a new goroutine for every incoming QUIC stream without imposing any limits on the number of concurrent streams or goroutines. A remote, unauthenticated attacker could open a large number of streams, leading to uncontrolled memory consumption and eventually causing an Out Of Memory (OOM) crash - especially in containerized or memory-constrained environments. The patch in version 1.12.2 introduces two key mitigation mechanisms: `max_streams`, which caps the number of concurrent QUIC streams per connection with a default value of `256`; and `worker_pool_size`, which Introduces a server-wide, bounded worker pool to process incoming streams with a default value of `1024`. This eliminates the 1:1 stream-to-goroutine model and ensures that CoreDNS remains resilient under high concurrency.  Some workarounds are available for those who are unable to upgrade. Disable QUIC support by removing or commenting out the `quic://` block in the Corefile, use container runtime resource limits to detect and isolate excessive memory usage, and/or monitor QUIC connection patterns and alert on anomalies.","title":"CVE description"}],"product_status":{"recommended":["SUSE Linux Enterprise Server 16.0:govulncheck-vulndb-0.0.20250814T182633-160000.1.2","openSUSE Tumbleweed:govulncheck-vulndb-0.0.20250612T141001-1.1"]},"references":[{"category":"external","summary":"CVE-2025-47950","url":"https://www.suse.com/security/cve/CVE-2025-47950"},{"category":"external","summary":"SUSE Security Ratings","url":"https://www.suse.com/support/security/rating/"},{"category":"external","summary":"SUSE Bug 1244331 for CVE-2025-47950","url":"https://bugzilla.suse.com/1244331"}],"remediations":[{"category":"vendor_fix","details":"To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n","product_ids":["SUSE Linux Enterprise Server 16.0:govulncheck-vulndb-0.0.20250814T182633-160000.1.2","openSUSE Tumbleweed:govulncheck-vulndb-0.0.20250612T141001-1.1"]}],"scores":[{"cvss_v3":{"baseScore":5.3,"baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"products":["SUSE Linux Enterprise Server 16.0:govulncheck-vulndb-0.0.20250814T182633-160000.1.2","openSUSE Tumbleweed:govulncheck-vulndb-0.0.20250612T141001-1.1"]}],"threats":[{"category":"impact","date":"2025-06-06T20:00:17Z","details":"moderate"}],"title":"CVE-2025-47950"}]}