{"id":"CVE-2021-36155","aliases":["EUVD-2023-1886","GHSA-rxmj-hg9v-vp3p"],"status":"published","title":"Uncontrolled Resource Consumption in LengthPrefixedMessageReader","description":"LengthPrefixedMessageReader in gRPC Swift 1.1.0 and earlier allocates buffers of arbitrary length, which allows remote attackers to cause uncontrolled resource consumption and deny service.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.02082,"percentile":0.81701,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-120","CWE-770"],"published":"2021-07-09T11:11:10Z","modified":"2026-10-20T10:54:47Z","fixes":[{"ecosystem":"SwiftURL","package":"github.com/grpc/grpc-swift","fixed_in":["1.2.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"SwiftURL","package":"github.com/grpc/grpc-swift","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.2.0"}]}]},{"source":"osv","ecosystem":"SwiftURL","package":"github.com/grpc/grpc-swift","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.2.0"}]}]}],"products":[{"vendor":"linuxfoundation","product":"grpc_swift"}],"references":[{"url":"https://github.com/grpc/grpc-swift/releases","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory"]},{"url":"https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35303","tags":["x_refsource_MISC","x_transferred","Mailing List","Third Party Advisory","advisory","web"]},{"url":"https://github.com/grpc/grpc-swift/security/advisories/GHSA-rxmj-hg9v-vp3p","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-36155","tags":["advisory"]},{"url":"https://github.com/grpc/grpc-swift/releases/tag/1.2.0","tags":["web"]},{"url":"https://github.com/advisories/GHSA-rxmj-hg9v-vp3p"},{"url":"https://github.com/grpc/grpc-swift","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2021-36155","description":"LengthPrefixedMessageReader in gRPC Swift 1.1.0 and earlier allocates buffers of arbitrary length, which allows remote attackers to cause uncontrolled resource consumption and deny service.","status":"published","published":"2021-07-09T11:11:10Z","modified":"2024-08-04T00:47:43.824Z","updated_at":"2026-11-02T14:33:06.32268Z"}],"euvd":[{"id":"EUVD-2023-1886","description":"LengthPrefixedMessageReader in gRPC Swift 1.1.0 and earlier allocates buffers of arbitrary length, which allows remote attackers to cause uncontrolled resource consumption and deny service.","status":"published","published":"2021-07-09T11:11:10Z","modified":"2024-08-04T00:47:43Z","updated_at":"2026-11-03T03:24:29.877227Z"}],"ghsa":[{"id":"GHSA-rxmj-hg9v-vp3p","title":"Uncontrolled Resource Consumption in LengthPrefixedMessageReader","description":"### Impact\n\nAffected gRPC Swift clients and servers are vulnerable to uncontrolled resource consumption attacks. Excessive memory may be allocated when parsing messages. This can lead to a denial of service.\n\n### Patches\n\nThe problem has been fixed in 1.2.0.\n\n### Workarounds\n\nNo workaround is available. Users must upgrade.","status":"published","published":"2023-06-09T19:32:11Z","modified":"2023-06-19T16:45:07Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-120","CWE-770"],"updated_at":"2026-11-02T14:36:55.184601Z"}],"nvd":[{"id":"CVE-2021-36155","description":"LengthPrefixedMessageReader in gRPC Swift 1.1.0 and earlier allocates buffers of arbitrary length, which allows remote attackers to cause uncontrolled resource consumption and deny service.","status":"published","published":"2021-07-09T12:15:08.127Z","modified":"2026-06-17T03:58:25.617Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:06:55.259633Z"}],"osv":[{"id":"CVE-2021-36155","description":"LengthPrefixedMessageReader in gRPC Swift 1.1.0 and earlier allocates buffers of arbitrary length, which allows remote attackers to cause uncontrolled resource consumption and deny service.","status":"published","published":"2021-07-09T12:15:08.127Z","modified":"2026-10-20T10:54:47.85707184Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:20.434873Z"},{"id":"GHSA-rxmj-hg9v-vp3p","title":"Uncontrolled Resource Consumption in LengthPrefixedMessageReader","description":"### Impact\n\nAffected gRPC Swift clients and servers are vulnerable to uncontrolled resource consumption attacks. Excessive memory may be allocated when parsing messages. This can lead to a denial of service.\n\n### Patches\n\nThe problem has been fixed in 1.2.0.\n\n### Workarounds\n\nNo workaround is available. Users must upgrade.","status":"published","published":"2023-06-09T19:32:11Z","modified":"2026-07-08T06:29:59.049314536Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-120","CWE-770"],"updated_at":"2026-11-02T15:46:56.639206Z"}]}}