{"items":[{"id":"NVI-00017694","kind":"vulnerability","title":" MessagePack's LZ4 decompression may fail with AccessViolationException after dereferencing memory from bad input","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-hv8m-jj95-wg3x","CVE-2026-48109"],"plain_summary":"GitHub lists this reviewed advisory for MessagePack, MessagePack. 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-49452fb94b2209c59bbbe8411f8826c9"],"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":"2026-06-25T15:01:14.000Z","value":"8.2 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-49452fb94b2209c59bbbe8411f8826c9"}],"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-49452fb94b2209c59bbbe8411f8826c9","url":"https://github.com/advisories/GHSA-hv8m-jj95-wg3x","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-hv8m-jj95-wg3x","publisher":"GitHub Advisory Database","observed_at":"2026-11-05T19:06:16.668Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-49452fb94b2209c59bbbe8411f8826c9"],"technology":"MessagePack","known_exclusions":[],"conditions_summary":"### Impact\n\nA vulnerability exists in the optional LZ4 decompression path used by MessagePack compression modes `Lz4Block` and `Lz4BlockArray`.\n\nThe decoder implementation is based on a deprecated fast-decompression algorithm that does not take a source-length bound. A remote attacker can send a crafted MessagePack payload with manipulated LZ4 token/length fields to force out-of-bounds reads from the compressed input buffer. In affected environments, this can trigger an `AccessViolationException` during decompression, causing process termination (denial of service). Under some conditions, limited unintended memory disclosure from over-read data may also be possible before failure.\n\nThis issue affects applications that deserialize untrusted data while LZ4 compression is enabled.\n\n### Patches\n\nThe v2 versions are patched as of 2.5.301.\nThe v3 versions are patched as of 3.1.7.\n\n### Workarounds\n\nInstead of upgrading, an application may take the following precautions:\n\n1. Disable LZ4 compression for untrusted input paths (`Lz4Block`, `Lz4BlockArray`).\n2. Only accept compressed payloads from strongly trusted producers.\n3. Isolate deserialization in a separate process/container with resta","public_affected_ranges":["< 2.5.301"]},{"certainty":"source_listed","source_ids":["sr-49452fb94b2209c59bbbe8411f8826c9"],"technology":"MessagePack","known_exclusions":[],"conditions_summary":"### Impact\n\nA vulnerability exists in the optional LZ4 decompression path used by MessagePack compression modes `Lz4Block` and `Lz4BlockArray`.\n\nThe decoder implementation is based on a deprecated fast-decompression algorithm that does not take a source-length bound. A remote attacker can send a crafted MessagePack payload with manipulated LZ4 token/length fields to force out-of-bounds reads from the compressed input buffer. In affected environments, this can trigger an `AccessViolationException` during decompression, causing process termination (denial of service). Under some conditions, limited unintended memory disclosure from over-read data may also be possible before failure.\n\nThis issue affects applications that deserialize untrusted data while LZ4 compression is enabled.\n\n### Patches\n\nThe v2 versions are patched as of 2.5.301.\nThe v3 versions are patched as of 3.1.7.\n\n### Workarounds\n\nInstead of upgrading, an application may take the following precautions:\n\n1. Disable LZ4 compression for untrusted input paths (`Lz4Block`, `Lz4BlockArray`).\n2. Only accept compressed payloads from strongly trusted producers.\n3. Isolate deserialization in a separate process/container with resta","public_affected_ranges":[">= 3.0.214-rc.1, < 3.1.7"]}],"null_published_at":"2026-11-05T19:10:21.453Z","source_updated_at":"2026-06-25T15:01:14.000Z","source_disclosed_at":"2026-06-11T20:34:10.000Z","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":"2026-11-05T19:06:16.668Z"}],"next_cursor":null,"snapshot_revision":"42594"}