pypdf: Possible large memory usage for large /ToUnicode streams (Follow-up 2)

CAO 7.5CVE-2026-102995 · GHSA-fp3h-c4fm-7vvf · PYSEC-2026-4154 · Công bố 30/09/2026 · cập nhật 05/10/2026

Tóm tắt nhanh

CVE-2026-102995 là lỗ hổng mức CAO (CVSS 7.5) ảnh hưởng pypdf, pypdf (pypdf project).
Xác suất bị khai thác trong 30 ngày tới (EPSS): 0.34%, cao hơn 27.6% các lỗ hổng khác.
Cách xử lý: cập nhật lên 6.18.1 hoặc mới hơn.

Gói / sản phẩm	Phiên bản bị ảnh hưởng	Phiên bản đã vá
pypdf PyPI	`< 6.18.1`	`6.18.1`
pypdf pypdf_project	`< 6.18.1`	`6.18.1`

Mô tả

Impact

An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the /ToUnicode entry of a font with unusually large values, for example during text extraction.

Patches

This has been fixed in pypdf==6.18.1.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #4071.

Mô tả của NVD

pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can place unusually large source-code or destination-string tokens in a font /ToUnicode mapping, causing pypdf/_cmap.py parse_bfchar to decode and retain oversized values during operations such as text extraction and consume excessive memory. This is a second follow-up to earlier /ToUnicode resource-consumption fixes and is limited to the remaining token-length path. This issue is fixed in version 6.18.1.