BUG: read_csv results in SIGSEGV #63089
Description
Pandas version checks
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I have checked that this issue has not already been reported.
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I have confirmed this bug exists on the latest version of pandas.
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I have confirmed this bug exists on the main branch of pandas.
Reproducible Example
import io import pandas as pd pd.read_csv(io.StringIO("""h 4e492493924924"""))Issue Description
Running the example results in SIGSEGV.
Expected Behavior
Running the example should not cause SIGSEGV.
Installed Versions
INSTALLED VERSIONS ------------------ commit : 9c8bc3e55188c8aff37207a74f1dd144980b8874 python : 3.12.10 python-bits : 64 OS : Linux OS-release : 6.8.0-87-generic Version : #88-Ubuntu SMP PREEMPT_DYNAMIC Sat Oct 11 09:28:41 UTC 2025 machine : x86_64 processor : byteorder : little LC_ALL : None LANG : C.UTF-8 LOCALE : C.UTF-8 pandas : 2.3.3 numpy : 2.3.4 pytz : 2025.2 dateutil : 2.9.0.post0 pip : 25.3 Cython : None sphinx : None IPython : 9.7.0 adbc-driver-postgresql: None adbc-driver-sqlite : None bs4 : None blosc : None bottleneck : None dataframe-api-compat : None fastparquet : None fsspec : None html5lib : None hypothesis : None gcsfs : None jinja2 : 3.1.6 lxml.etree : None matplotlib : None numba : None numexpr : None odfpy : None openpyxl : None pandas_gbq : None psycopg2 : None pymysql : None pyarrow : 22.0.0 pyreadstat : None pytest : None python-calamine : None pyxlsb : None s3fs : None scipy : 1.16.3 sqlalchemy : None tables : None tabulate : None xarray : None xlrd : None xlsxwriter : None zstandard : None tzdata : 2025.2 qtpy : None pyqt5 : None