{"items":[{"id":"NVI-00015235","kind":"vulnerability","title":"Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-4grm-h2qv-h6w6","CVE-2026-48748"],"plain_summary":"GitHub lists this reviewed advisory for io.netty:netty-codec-http3. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-0003a74d45a335491cc2599cfa94db92"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-08-04T21:50:04.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-469ccfa46dc11c51e08222a03efcd9ef"},{"kind":"EPSS","as_of":"2026-11-06T12:00:23.000Z","value":"0.392%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.33595. Missing scores are unknown.","source_id":"sr-0003a74d45a335491cc2599cfa94db92"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-469ccfa46dc11c51e08222a03efcd9ef","url":"https://github.com/advisories/GHSA-4grm-h2qv-h6w6","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-4grm-h2qv-h6w6","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T09:58:09.980Z"},{"id":"sr-0003a74d45a335491cc2599cfa94db92","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-48748","publisher":"FIRST EPSS","observed_at":"2026-11-06T20:58:43.532Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-469ccfa46dc11c51e08222a03efcd9ef"],"technology":"io.netty:netty-codec-http3","known_exclusions":[],"conditions_summary":"### Summary\nA memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OOM error.\n\n### Details\nThe vulnerability exists in `io.netty.handler.codec.http3.QpackDecoder#shouldWaitForDynamicTableUpdates`:\n\nIf a client sends a header referencing a table entry that the server hasn't received yet, the server must pause that stream and wait for the missing entry to arrive. To prevent attackers from exhausting resources by intentionally sending missing references, Netty limits the number of streams that can be blocked at the same time.\n\nHowever, the check is implemented as:\n\n```java\nif (blockedStreamsCount == maxBlockedStreams - 1) {\n```\n\nIf the server enables QPACK dynamic tables (by setting `HTTP3_SETTINGS_QPACK_MAX_TABLE_CAPACITY` > 0) but does not explicitly configure `HTTP3_SETTINGS_QPACK_BLOCKED_STREAMS`, it defaults to 0.\n\nWhen `maxBlockedStreams` is 0, the condition evaluates to `blockedStreamsCount == -1`. Since `blockedStreamsCount` starts at `0` and only increments, it never equals `-1`. This bypasses the limit, allowing an attacker to open an infinite number of streams that block indefinitely. Additio","public_affected_ranges":[">= 4.2.0.Final, <= 4.2.14.Final"]}],"null_published_at":"2026-11-07T22:29:23.464Z","source_updated_at":"2026-08-04T21:50:04.000Z","source_disclosed_at":"2026-06-15T20:43:13.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-03T09:58:09.980Z"},{"id":"NVI-00015235","kind":"vulnerability","title":"Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-4grm-h2qv-h6w6","CVE-2026-48748"],"plain_summary":"GitHub lists this reviewed advisory for io.netty:netty-codec-http3. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-469ccfa46dc11c51e08222a03efcd9ef"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-08-04T21:50:04.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-469ccfa46dc11c51e08222a03efcd9ef"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-469ccfa46dc11c51e08222a03efcd9ef","url":"https://github.com/advisories/GHSA-4grm-h2qv-h6w6","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-4grm-h2qv-h6w6","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T09:58:09.980Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-469ccfa46dc11c51e08222a03efcd9ef"],"technology":"io.netty:netty-codec-http3","known_exclusions":[],"conditions_summary":"### Summary\nA memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OOM error.\n\n### Details\nThe vulnerability exists in `io.netty.handler.codec.http3.QpackDecoder#shouldWaitForDynamicTableUpdates`:\n\nIf a client sends a header referencing a table entry that the server hasn't received yet, the server must pause that stream and wait for the missing entry to arrive. To prevent attackers from exhausting resources by intentionally sending missing references, Netty limits the number of streams that can be blocked at the same time.\n\nHowever, the check is implemented as:\n\n```java\nif (blockedStreamsCount == maxBlockedStreams - 1) {\n```\n\nIf the server enables QPACK dynamic tables (by setting `HTTP3_SETTINGS_QPACK_MAX_TABLE_CAPACITY` > 0) but does not explicitly configure `HTTP3_SETTINGS_QPACK_BLOCKED_STREAMS`, it defaults to 0.\n\nWhen `maxBlockedStreams` is 0, the condition evaluates to `blockedStreamsCount == -1`. Since `blockedStreamsCount` starts at `0` and only increments, it never equals `-1`. This bypasses the limit, allowing an attacker to open an infinite number of streams that block indefinitely. Additio","public_affected_ranges":[">= 4.2.0.Final, <= 4.2.14.Final"]}],"null_published_at":"2026-11-03T10:03:26.563Z","source_updated_at":"2026-08-04T21:50:04.000Z","source_disclosed_at":"2026-06-15T20:43:13.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-03T09:58:09.980Z"}],"next_cursor":null,"snapshot_revision":"42594"}