How severe is CVE-2026-84311?

CVE-2026-84311 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-84311 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-84311?

CVE-2026-84311 affects Pypdf Project Pypdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-84311?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-84311 published?

CVE-2026-84311 was published on 2026-09-01 and last updated on 2026-10-05.

CVE-2026-84311

CVE-2026-84311 is a low-severity vulnerability in Pypdf Project Pypdf with a CVSS 3.x base score of 3.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-834.

Key facts

Severity: Low (CVSS 3.x base score 3.3)
CVSS v4: 4.8
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-834
Affected product: Pypdf Project Pypdf
Published: 2026-09-01
Last modified: 2026-10-05

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.16.1, an attacker can craft a PDF that causes pypdf/_page.py PageObject._extract_text and PageObject.extract_xform_text to traverse a directed acyclic graph of reused form XObjects in which each form invokes a child multiple times, creating exponentially many traversal paths and causing long runtimes and large memory consumption. This issue is fixed in version 6.16.1.

Frequently asked questions

What is CVE-2026-84311?: pypdf is a free and open-source pure-python PDF library. Prior to 6.16.1, an attacker can craft a PDF that causes pypdf/_page.py PageObject._extract_text and PageObject.extract_xform_text to traverse a directed acyclic graph of reused form XObjects in which each form invokes a child multiple times, creating exponentially many traversal paths and causing long runtimes and large memory consumption. This issue is fixed in version 6.16.1.
How severe is CVE-2026-84311?: CVE-2026-84311 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-84311 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-84311?: CVE-2026-84311 affects Pypdf Project Pypdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-84311?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-84311 published?: CVE-2026-84311 was published on 2026-09-01 and last updated on 2026-10-05.

References

Affected products (1)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*

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