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Nikola Vouk commented on GUACAMOLE-711: --------------------------------------- I just tried with version 1.0.0. No seg fault so that's a plus. Still error in authentication protocols. The blacklist is a defensive feature for RealVNC to prevent DoS attacks and errors with VNC Clients. > segfault when connecting to RealVNC Server > ------------------------------------------ > > Key: GUACAMOLE-711 > URL: https://issues.apache.org/jira/browse/GUACAMOLE-711 > Project: Guacamole > Issue Type: Bug > Components: guacd > Affects Versions: 0.9.14 > Environment: ubuntu 18.04 > Reporter: Nikola Vouk > Priority: Blocker > > Guacd segfaults when connecting to RealVNC server in loop. I reduce protocol > support on RealVNC server to 3.8 and it still segfaults. > > Doesn't seem to work in any mode with RealVNC server (v6 latest) > > > > Jan 21 16:09:37 vormir guacd[25649]: Cursor rendering: local > Jan 21 16:09:37 vormir guacd[25649]: User > "@d3168c3d-c7bd-4f63-a92b-6bd9a8b5b8f3" joined connection > "$17f9006a-a75b-4e7b-a240-d59b8d5ba08d" (1 users now present) > Jan 21 16:09:37 vormir guacd[25649]: VNC server supports protocol version 5.0 > (viewer 3.8) > Jan 21 16:09:37 vormir guacd[25649]: We have 5 security types to read > Jan 21 16:09:37 vormir guacd[25649]: 0) Received security type 13 > Jan 21 16:09:37 vormir guacd[25649]: 1) Received security type 133 > Jan 21 16:09:37 vormir guacd[25649]: 2) Received security type 5 > Jan 21 16:09:37 vormir guacd[25649]: 3) Received security type 129 > Jan 21 16:09:37 vormir guacd[25649]: 4) Received security type 192 > Jan 21 16:09:37 vormir guacd[25649]: Unknown authentication scheme from VNC > server: 13, 133, 5, 129, 192 > Jan 21 16:09:37 vormir guacd[25649]: Unable to connect to VNC server. > Jan 21 16:09:41 vormir kernel: [2432033.730381] guacd[25652]: segfault at 10 > ip 00007f751eabcf32 sp 00007f751fcc5cb0 error 4 in > libguac-client-vnc.so.0.0.0[7f751eab7000+d000] > Jan 21 16:09:41 vormir guacd[23513]: Connection > "$17f9006a-a75b-4e7b-a240-d59b8d5ba08d" removed. > Jan 21 16:11:56 vormir guacd[23513]: Creating new client for protocol "vnc" > Jan 21 16:11:56 vormir guacd[23513]: Connection ID is > "$5e7d49fe-695d-44ae-8b96-6efc445cb40a" > Jan 21 16:11:56 vormir guacd[25663]: Cursor rendering: local > Jan 21 16:11:56 vormir guacd[25663]: User > "@7e346687-feba-4bd4-882f-615acad9bc90" joined connection > "$5e7d49fe-695d-44ae-8b96-6efc445cb40a" (1 users now present) > Jan 21 16:11:56 vormir guacd[25663]: VNC server supports protocol version 5.0 > (viewer 3.8) > Jan 21 16:11:56 vormir guacd[25663]: We have 5 security types to read > Jan 21 16:11:56 vormir guacd[25663]: 0) Received security type 13 > Jan 21 16:11:56 vormir guacd[25663]: 1) Received security type 133 > Jan 21 16:11:56 vormir guacd[25663]: 2) Received security type 5 > Jan 21 16:11:56 vormir guacd[25663]: 3) Received security type 129 > Jan 21 16:11:56 vormir guacd[25663]: 4) Received security type 192 > Jan 21 16:11:56 vormir guacd[25663]: Unknown authentication scheme from VNC > server: 13, 133, 5, 129, 192 > Jan 21 16:11:56 vormir guacd[25663]: Unable to connect to VNC server. > Jan 21 16:12:01 vormir kernel: [2432173.992924] guacd[25666]: segfault at 10 > ip 00007f751eabcf32 sp 00007f751f4c4cb0 error 4 in > libguac-client-vnc.so.0.0.0[7f751eab7000+d000] > Jan 21 16:12:01 vormir guacd[23513]: Connection > "$5e7d49fe-695d-44ae-8b96-6efc445cb40a" removed. > Jan 21 16:16:22 vormir guacd[23513]: Creating new client for protocol "vnc" > Jan 21 16:16:22 vormir guacd[23513]: Connection ID is > "$a86e97e8-0c9a-4b09-80f5-877cdaf99a72" > Jan 21 16:16:22 vormir guacd[25678]: Cursor rendering: local > Jan 21 16:16:22 vormir guacd[25678]: User > "@38a00a62-f7e0-4e09-ae9d-f89f849e849f" joined connection > "$a86e97e8-0c9a-4b09-80f5-877cdaf99a72" (1 users now present) > Jan 21 16:16:22 vormir guacd[25678]: VNC server supports protocol version 5.0 > (viewer 3.8) > Jan 21 16:16:22 vormir guacd[25678]: We have 4 security types to read > Jan 21 16:16:22 vormir guacd[25678]: 0) Received security type 13 > Jan 21 16:16:22 vormir guacd[25678]: 1) Received security type 133 > Jan 21 16:16:22 vormir guacd[25678]: 2) Received security type 5 > Jan 21 16:16:22 vormir guacd[25678]: 3) Received security type 129 > Jan 21 16:16:22 vormir guacd[25678]: Unknown authentication scheme from VNC > server: 13, 133, 5, 129 > Jan 21 16:16:22 vormir guacd[25678]: Unable to connect to VNC server. > > > > ..... > > > > > > an 21 17:10:56 vormir kernel: [2435708.568872] guacd[26638]: segfault at 10 > ip 00007f2ef2ab0f32 sp 00007f2ef34b8cb0 error 4 in > libguac-client-vnc.so.0.0.0[7f2ef2aab000+d000] > Jan 21 17:10:56 vormir guacd[25908]: Connection > "$4d08eb51-726a-4107-8aee-1407037e40e1" removed. > Jan 21 17:11:16 vormir guacd[25908]: Creating new client for protocol "vnc" > Jan 21 17:11:16 vormir guacd[25908]: Connection ID is > "$de564a19-20be-4530-910e-d7fe69e2d287" > Jan 21 17:11:16 vormir guacd[26648]: Cursor rendering: local > Jan 21 17:11:16 vormir guacd[26648]: User > "@b208221b-5700-4cfb-9c4b-f93b64d7a62e" joined connection > "$de564a19-20be-4530-910e-d7fe69e2d287" (1 users now present) > Jan 21 17:11:16 vormir guacd[26648]: VNC server supports protocol version 3.3 > (viewer 3.8) > Jan 21 17:11:16 vormir guacd[26648]: Selected Security Scheme 0 > Jan 21 17:11:16 vormir guacd[26648]: VNC connection failed: Too many security > failures > Jan 21 17:11:16 vormir guacd[26648]: Unable to connect to VNC server. > Jan 21 17:11:21 vormir kernel: [2435733.604227] guacd[26651]: segfault at 10 > ip 00007f2ef2ab0f32 sp 00007f2ef44bacb0 error 4 in > libguac-client-vnc.so.0.0.0[7f2ef2aab000+d000] > Jan 21 17:11:21 vormir guacd[25908]: Connection > "$de564a19-20be-4530-910e-d7fe69e2d287" removed. > Jan 21 17:11:41 vormir guacd[25908]: Creating new client for protocol "vnc" > Jan 21 17:11:41 vormir guacd[25908]: Connection ID is > "$7b6f08a7-b9c1-440e-9919-ab36efe1fe2c" > Jan 21 17:11:41 vormir guacd[26662]: Cursor rendering: local > Jan 21 17:11:41 vormir guacd[26662]: User > "@47f011ce-79d3-48df-84d2-6b67e9cf8d2d" joined connection > "$7b6f08a7-b9c1-440e-9919-ab36efe1fe2c" (1 users now present) > Jan 21 17:11:41 vormir guacd[26662]: VNC server supports protocol version 3.3 > (viewer 3.8) > Jan 21 17:11:41 vormir guacd[26662]: Selected Security Scheme 0 > Jan 21 17:11:41 vormir guacd[26662]: VNC connection failed: Too many security > failures > Jan 21 17:11:41 vormir guacd[26662]: Unable to connect to VNC server. > Jan 21 17:11:46 vormir kernel: [2435758.636422] guacd[26665]: segfault at 10 > ip 00007f2ef2ab0f32 sp 00007f2ef3cb9cb0 error 4 in > libguac-client-vnc.so.0.0.0[7f2ef2aab000+d000] > Jan 21 17:11:46 vormir guacd[25908]: Connection > "$7b6f08a7-b9c1-440e-9919-ab36efe1fe2c" removed. > Jan 21 17:12:06 vormir guacd[25908]: Creating new client for protocol "vnc" > Jan 21 17:12:06 vormir guacd[25908]: Connection ID is > "$3ecaad57-e9d4-4a35-8408-81615af9db9d" > Jan 21 17:12:06 vormir guacd[26675]: Cursor rendering: local > Jan 21 17:12:06 vormir guacd[26675]: User > "@19fbd4ab-69b2-4eb9-b339-87208346d309" joined connection > "$3ecaad57-e9d4-4a35-8408-81615af9db9d" (1 users now present) > Jan 21 17:12:06 vormir guacd[26675]: VNC server supports protocol version 3.3 > (viewer 3.8) > Jan 21 17:12:06 vormir guacd[26675]: Selected Security Scheme 0 > Jan 21 17:12:06 vormir guacd[26675]: VNC connection failed: Too many security > failures > Jan 21 17:12:06 vormir guacd[26675]: Unable to connect to VNC server. > Jan 21 17:12:11 vormir kernel: [2435783.667136] guacd[26678]: segfault at 10 > ip 00007f2ef2ab0f32 sp 00007f2ef34b8cb0 error 4 in > libguac-client-vnc.so.0.0.0[7f2ef2aab000+d000] > Jan 21 17:12:11 vormir guacd[25908]: Connection > "$3ecaad57-e9d4-4a35-8408-81615af9db9d" removed. > Jan 21 17:12:31 vormir guacd[25908]: Creating new client for protocol "vnc" > Jan 21 17:12:31 vormir guacd[25908]: Connection ID is > "$f86607c8-dbe7-4966-b37e-489ae8468da9" > Jan 21 17:12:31 vormir guacd[26688]: Cursor rendering: local > Jan 21 17:12:31 vormir guacd[26688]: User > "@b1c43690-91dc-4e12-bd69-649b4278cbfa" joined connection > "$f86607c8-dbe7-4966-b37e-489ae8468da9" (1 users now present) > Jan 21 17:12:31 vormir guacd[26688]: VNC server supports protocol version 3.3 > (viewer 3.8) > Jan 21 17:12:31 vormir guacd[26688]: Selected Security Scheme 0 > > 2515,1 93% -- This message was sent by Atlassian JIRA (v7.6.3#76005)