{"id":"CURL-CVE-2019-3822","summary":"NTLMv2 type-3 header stack buffer overflow","details":"libcurl contains a stack based buffer overflow vulnerability.\n\nThe function creating an outgoing NTLM type-3 header\n(`lib/vauth/ntlm.c:Curl_auth_create_ntlm_type3_message()`), generates the\nrequest HTTP header contents based on previously received data. The check that\nexists to prevent the local buffer from getting overflowed is implemented\nwrongly (using unsigned math) and as such it does not prevent the overflow\nfrom happening.\n\nThis output data can grow larger than the local buffer if large response data\nis extracted from a previous NTLMv2 header provided by the malicious or broken\nHTTP server.\n\nSuch large response data needs to be around 1000 bytes or more. The actual\npayload data copied to the target buffer comes from the NTLMv2 type-2 response\nheader.","aliases":["CVE-2019-3822"],"modified":"2026-05-18T13:46:06.173106Z","published":"2019-02-06T08:00:00Z","database_specific":{"severity":"High","last_affected":"7.63.0","URL":"https://curl.se/docs/CVE-2019-3822.json","CWE":{"desc":"Stack-based Buffer Overflow","id":"CWE-121"},"package":"curl","www":"https://curl.se/docs/CVE-2019-3822.html","affects":"both"},"affected":[{"ranges":[{"type":"SEMVER","events":[{"introduced":"7.36.0"},{"fixed":"7.64.0"}]},{"type":"GIT","repo":"https://github.com/curl/curl.git","events":[{"introduced":"86724581b6c02d160b52f817550cfdfc9c93af62"},{"fixed":"50c9484278c63b958655a717844f0721263939cc"}]}],"versions":["7.63.0","7.62.0","7.61.1","7.61.0","7.60.0","7.59.0","7.58.0","7.57.0","7.56.1","7.56.0","7.55.1","7.55.0","7.54.1","7.54.0","7.53.1","7.53.0","7.52.1","7.52.0","7.51.0","7.50.3","7.50.2","7.50.1","7.50.0","7.49.1","7.49.0","7.48.0","7.47.1","7.47.0","7.46.0","7.45.0","7.44.0","7.43.0","7.42.1","7.42.0","7.41.0","7.40.0","7.39.0","7.38.0","7.37.1","7.37.0","7.36.0","curl-7_63_0","curl-7_62_0","curl-7_61_1","curl-7_61_0","curl-7_60_0","curl-7_59_0","curl-7_58_0","curl-7_57_0","curl-7_56_1","curl-7_56_0","curl-7_55_1","curl-7_55_0","curl-7_54_1","curl-7_54_0","curl-7_53_1","curl-7_53_0","curl-7_52_1","curl-7_52_0","curl-7_51_0","curl-7_50_3","curl-7_50_2","curl-7_50_1","curl-7_50_0","curl-7_49_1","curl-7_49_0","curl-7_48_0","curl-7_47_1","curl-7_47_0","curl-7_46_0","curl-7_45_0","curl-7_44_0","curl-7_43_0","curl-7_42_0","curl-7_41_0","curl-7_40_0","curl-7_39_0","curl-7_38_0","curl-7_37_1","curl-7_37_0","curl-7_36_0"],"database_specific":{"source":"https://curl.se/docs/CURL-CVE-2019-3822.json","vanir_signatures_modified":"2026-05-18T13:46:06Z","vanir_signatures":[{"signature_type":"Line","signature_version":"v1","id":"CURL-CVE-2019-3822-0fb0f4e0","target":{"file":"lib/vauth/ntlm.c"},"deprecated":false,"source":"https://github.com/curl/curl.git/commit/50c9484278c63b958655a717844f0721263939cc","digest":{"threshold":0.9,"line_hashes":["46522549148290454789925570788080158728","49236166746968004033894625933615643172","293989637352139989590772450278867974609","337876479484979625219132730045572941827","28263089313798147067029949814912665161","73333534050834162111357397437957432721","272835995896107667374360360978373141065","172736422550849646938343555519740730524"]}},{"signature_type":"Function","signature_version":"v1","id":"CURL-CVE-2019-3822-4f5c57d6","target":{"function":"Curl_auth_create_ntlm_type3_message","file":"lib/vauth/ntlm.c"},"deprecated":false,"source":"https://github.com/curl/curl.git/commit/50c9484278c63b958655a717844f0721263939cc","digest":{"length":5186,"function_hash":"281456879565379301859239210676266882046"}}]}}],"schema_version":"1.7.5","credits":[{"name":"Wenxiang Qian of Tencent Blade Team","type":"FINDER"},{"name":"Daniel Stenberg","type":"REMEDIATION_DEVELOPER"},{"name":"Huzaifa Sidhpurwala","type":"OTHER"}]}