CVE-2023-36807

Infinite Loop when reading malformed objects in pypdf

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track*

*SSVC

Descriptions

pypdf is a pure-python PDF library capable of splitting, merging, cropping, and transforming the pages of PDF files. In version 2.10.5 an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case if the user extracted metadata from such a malformed PDF. Versions prior to 2.10.5 throw an error, but do not hang forever. This issue was fixed with https://github.com/py-pdf/pypdf/pull/1331 which has been included in release 2.10.6. Users are advised to upgrade. Users unable to upgrade should modify `PyPDF2/generic/_data_structures.py::read_object` to an an error throwing case. See GHSA-hm9v-vj3r-r55m for details.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

* Common Vulnerability Scoring System

SSVC

Decision:Track*

Exploitation

Poc

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2023-06-27 CVE Reserved
2023-06-30 CVE Published
2024-07-06 EPSS Updated
2024-11-06 CVE Updated
2024-11-06 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')

CAPEC

References (3)

URL	Tag	Source

URL	Date	SRC
https://github.com/py-pdf/pypdf/issues/1329	2024-11-06
https://github.com/py-pdf/pypdf/security/advisories/GHSA-hm9v-vj3r-r55m	2024-11-06

URL	Date	SRC
https://github.com/py-pdf/pypdf/pull/1331	2023-07-10

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Pypdf Project Search vendor "Pypdf Project"		Pypdf Search vendor "Pypdf Project" for product "Pypdf"				2.10.5 Search vendor "Pypdf Project" for product "Pypdf" and version "2.10.5"		-		Affected