{"items":[{"id":"NVI-00018388","kind":"vulnerability","title":"Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-x4gw-5cx5-pgmh","CVE-2026-45416"],"plain_summary":"GitHub lists this reviewed advisory for io.netty:netty-handler, io.netty:netty-handler. 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-1b036c071dc5f297bba20b09c4b256bb"],"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":"2026-06-12T19:29:22.000Z","value":"7.5 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-1b036c071dc5f297bba20b09c4b256bb"}],"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-1b036c071dc5f297bba20b09c4b256bb","url":"https://github.com/advisories/GHSA-x4gw-5cx5-pgmh","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-x4gw-5cx5-pgmh","publisher":"GitHub Advisory Database","observed_at":"2026-11-06T15:12:54.193Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-1b036c071dc5f297bba20b09c4b256bb"],"technology":"io.netty:netty-handler","known_exclusions":[],"conditions_summary":"SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates `ctx.alloc().buffer(handshakeLength)` (line 161). The guard at line 140 is `handshakeLength > maxClientHelloLength && maxClientHelloLength != 0`, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes.","public_affected_ranges":[">= 4.2.0.Final, <= 4.2.14.Final"]},{"certainty":"source_listed","source_ids":["sr-1b036c071dc5f297bba20b09c4b256bb"],"technology":"io.netty:netty-handler","known_exclusions":[],"conditions_summary":"SslClientHelloHandler.decode() reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates `ctx.alloc().buffer(handshakeLength)` (line 161). The guard at line 140 is `handshakeLength > maxClientHelloLength && maxClientHelloLength != 0`, and the commonly-used SniHandler/AbstractSniHandler constructors (SniHandler(Mapping), SniHandler(AsyncMapping), AbstractSniHandler()) pass maxClientHelloLength=0 and handshakeTimeoutMillis=0, so the length guard is disabled and no timeout is scheduled. A 16 MiB request exceeds the default pooled chunk size and becomes a huge/unpooled allocation performed immediately. The buffer is retained in the handler until the channel closes.","public_affected_ranges":["<= 4.1.134.Final"]}],"null_published_at":"2026-11-07T07:07:39.830Z","source_updated_at":"2026-06-12T19:29:22.000Z","source_disclosed_at":"2026-06-08T23:01:04.000Z","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":"2026-11-06T15:12:54.193Z"}],"next_cursor":null,"snapshot_revision":"42594"}