{"id":"CVE-2021-43839","aliases":["EUVD-2022-0577","GHSA-f854-hpxv-cw9r"],"status":"published","title":"Drainage of FeeCollector's Block Transaction Fees","description":"Cronos is a commercial implementation of a blockchain. In Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx. This problem has been patched in Cronos v0.6.5. There are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.01356,"percentile":0.71875,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-670"],"published":"2021-12-21T16:50:12Z","modified":"2026-10-24T10:50:26Z","fixes":[{"ecosystem":"Go","package":"github.com/crypto-org-chain/cronos","fixed_in":["0.6.5"],"sources":["ghsa","osv"]},{"ecosystem":"Go","package":"github.com/tharsis/ethermint","fixed_in":["0.10.0","0.7.3"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"github.com/crypto-org-chain/cronos","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.6.5"}]}]},{"source":"ghsa","ecosystem":"Go","package":"github.com/tharsis/ethermint","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.8.0"},{"fixed":"0.10.0"}]}]},{"source":"ghsa","ecosystem":"Go","package":"github.com/tharsis/evmos","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.4.2"}]}]},{"source":"ghsa","ecosystem":"Go","package":"github.com/tharsis/ethermint","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.7.3"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/crypto-org-chain/cronos","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.6.5"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/tharsis/ethermint","ranges":[{"type":"SEMVER","events":[{"introduced":"0.8.0"},{"fixed":"0.10.0"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/tharsis/evmos","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"last_affected":"0.4.2"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/tharsis/ethermint","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.7.3"}]}]}],"products":[{"vendor":"crypto","product":"cronos"},{"vendor":"crypto","product":"ethermint"},{"vendor":"crypto","product":"evmos"},{"vendor":"crypto-org-chain","product":"cronos"},{"vendor":"i2a","product":"cronos"}],"references":[{"url":"https://github.com/crypto-org-chain/cronos/security/advisories/GHSA-f854-hpxv-cw9r","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://github.com/crypto-org-chain/cronos/pull/270","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/crypto-org-chain/cronos/commit/150ef237b37ac28c8136e1c0f494932860b9ebe8","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43839","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-f854-hpxv-cw9r"},{"url":"https://github.com/crypto-org-chain/cronos","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2021-43839","title":"Drainage of FeeCollector's Block Transaction Fees","description":"Cronos is a commercial implementation of a blockchain. In Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx. This problem has been patched in Cronos v0.6.5. There are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.","status":"published","published":"2021-12-21T16:50:12Z","modified":"2024-08-04T04:10:17.113Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-670"],"updated_at":"2026-11-02T14:32:56.689433Z"}],"euvd":[{"id":"EUVD-2022-0577","description":"Cronos is a commercial implementation of a blockchain. In Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx. This problem has been patched in Cronos v0.6.5. There are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.","status":"published","published":"2021-12-21T16:50:12Z","modified":"2024-08-04T04:10:17Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:24:12.599691Z"}],"ghsa":[{"id":"GHSA-f854-hpxv-cw9r","title":"Drainage of FeeCollector's Block Transaction Fees in cronos","description":"### Impact\nIn Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx.\n\nUser funds and balances are safe.\n\n\n### Patches\nThis problem has been patched in Cronos v0.6.5 on the mempool level.\nThe next network upgrade with consensus-breaking changes will patch it on the consensus level.\n\n### Workarounds\nThere are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.\n\n### Credits\nThank you to @zb3 for reporting this issue on [Cronos Immunefi Bug Bounty Program](https://immunefi.com/bounty/cronos/), to @cyril-crypto for reproducing the issue and to @yihuang and @thomas-nguy for patching the issue on the CheckTx (mempool) and the DeliverTx (consensus) levels.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open a discussion in [crypto-org-chain/cronos](https://github.com/crypto-org-chain/cronos/discussions/new)\n* Email us at [chain@crypto.org](mailto:chain@crypto.org)\n","status":"published","published":"2022-01-06T18:30:54Z","modified":"2023-02-03T05:04:06Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-670"],"updated_at":"2026-11-02T14:36:41.967989Z"}],"nvd":[{"id":"CVE-2021-43839","description":"Cronos is a commercial implementation of a blockchain. In Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx. This problem has been patched in Cronos v0.6.5. There are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.","status":"published","published":"2021-12-21T17:15:08.413Z","modified":"2026-06-17T04:11:32.783Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high","assessor":"secondary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-670"],"updated_at":"2026-11-02T14:07:02.566991Z"}],"osv":[{"id":"CVE-2021-43839","description":"Cronos is a commercial implementation of a blockchain. In Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx. This problem has been patched in Cronos v0.6.5. There are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.","status":"published","published":"2021-12-21T17:15:08.413Z","modified":"2026-10-24T10:50:26.539331363Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:21.877444Z"},{"id":"GHSA-f854-hpxv-cw9r","title":"Drainage of FeeCollector's Block Transaction Fees in cronos","description":"### Impact\nIn Cronos nodes running versions before v0.6.5, it is possible to take transaction fees from Cosmos SDK's FeeCollector for the current block by sending a custom crafted MsgEthereumTx.\n\nUser funds and balances are safe.\n\n\n### Patches\nThis problem has been patched in Cronos v0.6.5 on the mempool level.\nThe next network upgrade with consensus-breaking changes will patch it on the consensus level.\n\n### Workarounds\nThere are no tested workarounds. All validator node operators are recommended to upgrade to Cronos v0.6.5 at their earliest possible convenience.\n\n### Credits\nThank you to @zb3 for reporting this issue on [Cronos Immunefi Bug Bounty Program](https://immunefi.com/bounty/cronos/), to @cyril-crypto for reproducing the issue and to @yihuang and @thomas-nguy for patching the issue on the CheckTx (mempool) and the DeliverTx (consensus) levels.\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open a discussion in [crypto-org-chain/cronos](https://github.com/crypto-org-chain/cronos/discussions/new)\n* Email us at [chain@crypto.org](mailto:chain@crypto.org)\n","status":"published","published":"2022-01-06T18:30:54Z","modified":"2026-07-08T06:29:14.059124576Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"high"}],"cwes":["CWE-670"],"updated_at":"2026-11-02T15:46:46.006631Z"}]}}