Vulnerability in Py-pdf Pypdf
CVE-2026-48156
pypdf is a free and open-source pure-python PDF library. Prior to 6.12.0, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires cross-reference streams with /W [0 0 0] values and large /Size va…
EPSS: 0.000 (1.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L.
Affected products
- Py-pdf Pypdf — versions < 6.12.0
- Pypdf_project Pypdf
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-48156?
- CVE-2026-48156 is a low-severity vulnerability in Py-pdf Pypdf, classified under Excessive Iteration. CVSS score: 3.3/10. Published 2026-05-28.
- How severe is CVE-2026-48156?
- Low severity. CVSS v3 base score is 3.3 out of 10.