websock server - Case 6.2.3 : Pass - 2 ms @ 2026-01-07T13:37:20.600Z
Case Description
Send a valid UTF-8 text message in fragments of 1 octet, resulting in frames ending on positions which are not code point ends.
MESSAGE:
Hello-µ@ßöäüàá-UTF-8!!
48656c6c6f2dc2b540c39fc3b6c3a4c3bcc3a0c3a12d5554462d382121
Case Expectation
The message is echo'ed back to us.
Case Outcome
Actual events match at least one expected.
Expected:
{'OK': [('message', u'Hello-\xb5@\xdf\xf6\xe4\xfc\xe0\xe1-UTF-8!!', False)]}
Observed:
[('message', u'Hello-\xb5@\xdf\xf6\xe4\xfc\xe0\xe1-UTF-8!!', False)]
Case Closing Behavior
The spec requires the connection to be failed cleanly here (UNCLEAN)
GET /ws HTTP/1.1 User-Agent: AutobahnTestSuite/25.10.1-0.10.9 Host: 127.0.0.1:8888 Upgrade: WebSocket Connection: Upgrade Pragma: no-cache Cache-Control: no-cache Sec-WebSocket-Key: K7bCb+tAjAQt6aKw9wOD/Q== Sec-WebSocket-Version: 13
HTTP/1.1 101 Switching Protocols Date: Wed, 07 Jan 2026 13:37:20 GMT Connection: Upgrade Upgrade: websocket Sec-Websocket-Accept: kweAboiRYYqdS76wIpjlciIdDTY=
| Key | Value | Description |
| isServer | False | True, iff I (the fuzzer) am a server, and the peer is a client. |
| closedByMe | True | True, iff I have initiated closing handshake (that is, did send close first). |
| failedByMe | False | True, iff I have failed the WS connection (i.e. due to protocol error). Failing can be either by initiating closing handshake or brutal drop TCP. |
| droppedByMe | False | True, iff I dropped the TCP connection. |
| wasClean | False | True, iff full WebSocket closing handshake was performed (close frame sent and received) _and_ the server dropped the TCP (which is its responsibility). |
| wasNotCleanReason | peer dropped the TCP connection without previous WebSocket closing handshake | When wasClean == False, the reason what happened. |
| wasServerConnectionDropTimeout | False | When we are a client, and we expected the server to drop the TCP, but that didn't happen in time, this gets True. |
| wasOpenHandshakeTimeout | False | When performing the opening handshake, but the peer did not finish in time, this gets True. |
| wasCloseHandshakeTimeout | False | When we initiated a closing handshake, but the peer did not respond in time, this gets True. |
| localCloseCode | 1000 | The close code I sent in close frame (if any). |
| localCloseReason | None | The close reason I sent in close frame (if any). |
| remoteCloseCode | None | The close code the peer sent me in close frame (if any). |
| remoteCloseReason | None | The close reason the peer sent me in close frame (if any). |
| Chop Size | Count | Octets |
| 31 | 1 | 31 |
| 166 | 1 | 166 |
| Total | 2 | 197 |
| Chop Size | Count | Octets |
| 6 | 1 | 6 |
| 7 | 29 | 203 |
| 8 | 1 | 8 |
| 244 | 1 | 244 |
| Total | 32 | 461 |
| Opcode | Count |
| 1 | 1 |
| Total | 1 |
| Opcode | Count |
| 0 | 29 |
| 1 | 1 |
| 8 | 1 |
| Total | 31 |
000 TX OCTETS: 474554202f777320485454502f312e310d0a557365722d4167656e743a204175746f6261686e5465737453756974652f3235
2e31302e312d302e31302e390d0a ...
001 RX OCTETS: 485454502f312e312031303120537769746368696e672050726f746f636f6c730d0a446174653a205765642c203037204a61
6e20323032362031333a33373a32 ...
002 TX FRAME : OPCODE=1, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=3d09f452, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
H
003 TX OCTETS: 01813d09f45275
004 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=cfacd6fc, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
e
005 TX OCTETS: 0081cfacd6fcaa
006 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=49717f19, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
l
007 TX OCTETS: 008149717f1925
008 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=c8e06ded, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
l
009 TX OCTETS: 0081c8e06deda4
010 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=c7b9e86a, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
o
011 TX OCTETS: 0081c7b9e86aa8
012 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=e926c63d, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
-
013 TX OCTETS: 0081e926c63dc4
014 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=8dc1c0e8, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc2
015 TX OCTETS: 00818dc1c0e84f
016 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=01da8bcb, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xb5
017 TX OCTETS: 008101da8bcbb4
018 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=2ffa1a03, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
@
019 TX OCTETS: 00812ffa1a036f
020 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=86bc4904, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
021 TX OCTETS: 008186bc490445
022 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=c5b166fe, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0x9f
023 TX OCTETS: 0081c5b166fe5a
024 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=64ca400f, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
025 TX OCTETS: 008164ca400fa7
026 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=49605254, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xb6
027 TX OCTETS: 008149605254ff
028 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=a7c01474, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
029 TX OCTETS: 0081a7c0147464
030 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=f71fcb9b, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xa4
031 TX OCTETS: 0081f71fcb9b53
032 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=65b85360, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
033 TX OCTETS: 008165b85360a6
034 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=7d7ae659, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xbc
035 TX OCTETS: 00817d7ae659c1
036 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=f9ce3a63, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
037 TX OCTETS: 0081f9ce3a633a
038 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=5ca6fe38, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xa0
039 TX OCTETS: 00815ca6fe38fc
040 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=da151ebe, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xc3
041 TX OCTETS: 0081da151ebe19
042 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=6ae7b42d, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0xa1
043 TX OCTETS: 00816ae7b42dcb
044 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=39757d56, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
-
045 TX OCTETS: 008139757d5614
046 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=f028b03d, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
U
047 TX OCTETS: 0081f028b03da5
048 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=051d6bec, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
T
049 TX OCTETS: 0081051d6bec51
050 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=ded50a2b, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
F
051 TX OCTETS: 0081ded50a2b98
052 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=9f621aac, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
-
053 TX OCTETS: 00819f621aacb2
054 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=461dc93d, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
8
055 TX OCTETS: 0081461dc93d7e
056 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=1bcbf3ca, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
!
057 TX OCTETS: 00811bcbf3ca3a
058 TX FRAME : OPCODE=0, FIN=False, RSV=0, PAYLOAD-LEN=1, MASK=14883966, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
!
059 TX OCTETS: 00811488396635
060 TX FRAME : OPCODE=0, FIN=True, RSV=0, PAYLOAD-LEN=0, MASK=706f74c3, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
061 TX OCTETS: 8080706f74c3
062 CLOSE CONNECTION AFTER 1.000000 sec
063 RX OCTETS: 811d48656c6c6f2dc2b540c39fc3b6c3a4c3bcc3a0c3a12d5554462d382121
064 RX FRAME : OPCODE=1, FIN=True, RSV=0, PAYLOAD-LEN=29, MASKED=False, MASK=None
Hello-µ@ßöäüàá-UTF-8!!
065 TX FRAME : OPCODE=8, FIN=True, RSV=0, PAYLOAD-LEN=2, MASK=0a099c83, PAYLOAD-REPEAT-LEN=None, CHOPSIZE=None, SYNC=False
0x03e8
066 TX OCTETS: 88820a099c8309e1
067 TCP DROPPED BY PEER