CVE-2026-27628
pypdf has a possible infinite loop when loading circular /Prev entries in cross-reference streams
Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually.
INFO
Published Date :
Feb. 25, 2026, 3:16 a.m.
Last Modified :
Feb. 27, 2026, 8:21 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | LOW | [email protected] |
Solution
- Update pypdf to version 6.7.2 or later.
- Apply the patch manually if updating is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-27628.
| URL | Resource |
|---|---|
| https://github.com/py-pdf/pypdf/commit/f0a462d36971cf077d74492a348d0d06fd60ea4d | |
| https://github.com/py-pdf/pypdf/issues/3654 | Issue TrackingPatch |
| https://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35 | PatchVendor Advisory |
| https://github.com/py-pdf/pypdf/issues/3654 | Issue TrackingPatch |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-27628 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-27628
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-27628 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-27628 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Feb. 27, 2026
Action Type Old Value New Value Added Reference https://github.com/py-pdf/pypdf/commit/f0a462d36971cf077d74492a348d0d06fd60ea4d Removed Reference https://github.com/py-pdf/pypdf/commit/0fbd95938724ad2d72688d4112207c0590f0483f Removed Reference Type https://github.com/py-pdf/pypdf/commit/0fbd95938724ad2d72688d4112207c0590f0483f Types: Patch -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Feb. 25, 2026
Action Type Old Value New Value Added Reference https://github.com/py-pdf/pypdf/issues/3654 -
Initial Analysis by [email protected]
Feb. 25, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:* versions up to (excluding) 6.7.2 Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/commit/0fbd95938724ad2d72688d4112207c0590f0483f Types: Patch Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/issues/3654 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35 Types: Patch, Vendor Advisory -
New CVE Received by [email protected]
Feb. 25, 2026
Action Type Old Value New Value Added Description pypdf is a free and open-source pure-python PDF library. Prior to 6.7.2, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires reading the file. This has been fixed in pypdf 6.7.2. As a workaround, one may apply the patch manually. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-835 Added Reference https://github.com/py-pdf/pypdf/commit/0fbd95938724ad2d72688d4112207c0590f0483f Added Reference https://github.com/py-pdf/pypdf/issues/3654 Added Reference https://github.com/py-pdf/pypdf/security/advisories/GHSA-2rw7-x74f-jg35