Is CVE-2026-115580 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-115580 being exploited in the wild.

How severe is CVE-2026-115580?

High severity, with a CVSS score of 4, published 23 October 2026.

Which products and versions are affected?

Pypdf before 6.21.2; pypdf (PyPI) < 6.21.2, ECOSYSTEM:introduced=0,fixed=6.21.2.

Is there a fix for CVE-2026-115580?

Yes. pypdf (PyPI): upgrade to 6.21.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-115580 attacked?

It is attacked over the network.

Am I affected by CVE-2026-115580?

Check whether you run Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-115580: pypdf ReDoS in cross-reference table parsing

Q: Is there a fix for CVE-2026-115580?

Yes. pypdf (PyPI): upgrade to 6.21.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-115580 attacked?

It is attacked over the network.

Q: Am I affected by CVE-2026-115580?

Check whether you run Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-115580 · Severity: high · CVSS 4 · Published 2026-10-23

pypdf is a Python library for reading and writing PDF files. An attacker can craft a malicious PDF with a cross-reference table that claims to contain more entries than the file can actually hold, causing the library to perform excessive processing and consume significant CPU time when opening the file. This results in a denial-of-service condition that can freeze applications using the library.

Technologies: Pypdf, pypdf (PyPI). Vendors: Pypdf, PyPI.

Quick answers

Is CVE-2026-115580 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-115580 being exploited in the wild.
How severe is CVE-2026-115580?: High severity, with a CVSS score of 4, published 23 October 2026.
Which products and versions are affected?: Pypdf before 6.21.2; pypdf (PyPI) < 6.21.2, ECOSYSTEM:introduced=0,fixed=6.21.2.
Is there a fix for CVE-2026-115580?: Yes. pypdf (PyPI): upgrade to 6.21.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-115580 attacked?: It is attacked over the network.
Am I affected by CVE-2026-115580?: Check whether you run Pypdf or pypdf (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

pypdf (PyPI): upgrade to 6.21.2 or later
```
pip install "pypdf>=6.21.2"
```

Technical details

The vulnerability is a regular expression denial of service (ReDoS) attack vector triggered when parsing standard cross-reference (xref) tables in PDF files. When a crafted PDF declares an entry count that exceeds the actual file size, the parsing logic attempts to process non-existent data, leading to algorithmic complexity and long runtimes. The fix limits the xref table size to the actual file size as a baseline constraint.

Affected products

pypdf pypdf before 6.21.2

Identifiers

CVE-2026-115580
GHSA-gmh7-3g9r-mjh5

Timeline

2026-10-23: disclosed
2026-10-21: patched

References

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