{"id":"CVE-2021-33879","aliases":["EUVD-2021-20553","GHSA-p52r-cj24-79f7"],"status":"published","title":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A...","description":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A malicious attacker in an MITM position could spoof the contents of an XML document describing an update package, replacing a download URL with one pointing to an arbitrary Windows executable. Because the only integrity check would be a comparison of the downloaded file's MD5 checksum to the one contained within the XML document, the downloaded executable would then be executed on the victim's machine.","severity":{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.012,"percentile":0.68434,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":false},"cwes":["CWE-494"],"published":"2021-06-06T19:25:23Z","modified":"2026-06-17T03:55:19Z","exploits":[{"source":"pocgithub","id":"mmiszczyk/cve-2021-33879","title":"mmiszczyk/cve-2021-33879","date":"2021-06-06","url":"https://github.com/mmiszczyk/cve-2021-33879"}],"products":[{"vendor":"tencent","product":"gameloop"}],"references":[{"url":"https://www.gameloop.com","tags":["x_refsource_MISC","x_transferred","Vendor Advisory"]},{"url":"https://github.com/mmiszczyk/cve-2021-33879","tags":["x_refsource_MISC","x_transferred","Exploit","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-33879"},{"url":"https://github.com/advisories/GHSA-p52r-cj24-79f7"}],"sources":{"cve":[{"id":"CVE-2021-33879","description":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A malicious attacker in an MITM position could spoof the contents of an XML document describing an update package, replacing a download URL with one pointing to an arbitrary Windows executable. Because the only integrity check would be a comparison of the downloaded file's MD5 checksum to the one contained within the XML document, the downloaded executable would then be executed on the victim's machine.","status":"published","published":"2021-06-06T19:25:23Z","modified":"2024-08-04T00:05:51.646Z","updated_at":"2026-11-02T14:33:10.204494Z"}],"euvd":[{"id":"EUVD-2021-20553","description":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A malicious attacker in an MITM position could spoof the contents of an XML document describing an update package, replacing a download URL with one pointing to an arbitrary Windows executable. Because the only integrity check would be a comparison of the downloaded file's MD5 checksum to the one contained within the XML document, the downloaded executable would then be executed on the victim's machine.","status":"published","published":"2021-06-06T19:25:23Z","modified":"2024-08-04T00:05:51Z","updated_at":"2026-11-03T03:24:33.318275Z"}],"ghsa":[{"id":"GHSA-p52r-cj24-79f7","title":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A...","description":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A malicious attacker in an MITM position could spoof the contents of an XML document describing an update package, replacing a download URL with one pointing to an arbitrary Windows executable. Because the only integrity check would be a comparison of the downloaded file's MD5 checksum to the one contained within the XML document, the downloaded executable would then be executed on the victim's machine.","status":"published","published":"2022-05-24T19:04:09Z","modified":"2023-01-29T05:06:27Z","cwes":["CWE-494"],"updated_at":"2026-11-02T14:46:01.927509Z"}],"nvd":[{"id":"CVE-2021-33879","description":"Tencent GameLoop before 4.1.21.90 downloaded updates over an insecure HTTP connection. A malicious attacker in an MITM position could spoof the contents of an XML document describing an update package, replacing a download URL with one pointing to an arbitrary Windows executable. Because the only integrity check would be a comparison of the downloaded file's MD5 checksum to the one contained within the XML document, the downloaded executable would then be executed on the victim's machine.","status":"published","published":"2021-06-06T20:15:07.613Z","modified":"2026-06-17T03:55:19.403Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":6.8,"vector":"AV:N/AC:M/Au:N/C:P/I:P/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-494"],"updated_at":"2026-11-02T14:06:54.439974Z"}]}}