{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-42530: NGINX Open-Source ngx_http_v3_module vulnerability","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-42530","status":"final","version":"1","initial_release_date":"2026-06-17T14:04:32.173Z","current_release_date":"2026-06-17T15:43:38.758Z","revision_history":[{"date":"2026-06-17T14:04:32.173Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.  \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-42530 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-42530"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-42530"},{"category":"external","summary":"my.f5.com","url":"https://my.f5.com/manage/s/article/K000161616"}]},"product_tree":{"branches":[{"category":"vendor","name":"F5","branches":[{"category":"product_name","name":"NGINX Open Source","branches":[{"category":"product_version_range","name":">=1.31.0 <1.31.2","product":{"name":"F5 NGINX Open Source >=1.31.0 <1.31.2","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-42530","title":"NGINX Open-Source ngx_http_v3_module vulnerability","notes":[{"category":"description","text":"NGINX Open Source has a vulnerability in the ngx_http_v3_module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This may cause a Use-after-Free in the NGINX worker process leading to a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR.  \n\n\nNote: Software versions which have reached End of Technical Support (EoTS) are not evaluated.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1"]},"scores":[{"cvss_v4":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","baseScore":9.2,"baseSeverity":"CRITICAL"},"products":["CSAFPID-1"]}],"remediations":[{"category":"vendor_fix","details":"Update to a fixed version: 1.31.2.","product_ids":["CSAFPID-1"]}]}]}