fortra/impacket

TDS: Unknown Token 0 / ac

Open

#879 opened on Jun 9, 2020

View on GitHub
 (1 comment) (0 reactions) (0 assignees)Python (3,421 forks)batch import
enhancementhelp wanted

Repository metrics

Stars
 (12,244 stars)
PR merge metrics
 (Avg merge 30d 8h) (10 merged PRs in 30d)

Description

Configuration

impacket version: 0.9.21 Python version: 3.7.7 Target OS: Ubuntu 18.04

Debug Output With Command String

i.e.
smbexec -debug domain/user:password@127.0.0.1

>>> tds.MSSQL('bla').parseReply(b"\xac\x0d\x00\x00\x01\x00\x00\x00\x00\x26\x04\x04\x0c\x00\x00\x00\xfe\x00\x00\xe0\x00\x00\x00\x00\x00")
ERROR:impacket:Unknown Token ac
{}

Additional context

This buffer is a 0xac token type taken from a pcap of TDS version 7.1. I expected token values 0xac (TDS_PARAM_TOKEN) and 0x00 (TVP_END_TOKEN) to be parsed.

Contributor guide

Research direction
Investigate the TDS reply parsing code in tds.py, add support for token 0xac (TDS PARAM TOKEN) and token 0x00 (TVP END TOKEN). Consult TDS protocol specification for these tokens.
Tech stack
python
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
Python
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75