Is CVE-2026-31899 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-31899 being exploited in the wild.

How severe is CVE-2026-31899?

High severity, with a CVSS score of 7.5, published 13 March 2026.

Which products and versions are affected?

CairoSVG (PyPI) <= 2.8.2, ECOSYSTEM:introduced=0,fixed=2.9.0.

Is there a fix for CVE-2026-31899?

Yes. CairoSVG (PyPI): upgrade to 2.9.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-31899 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-31899?

Check whether you run CairoSVG (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-2026-31899: Kozea CairoSVG exponential denial of service in defs.py

Q: Which products and versions are affected?

CairoSVG (PyPI) <= 2.8.2, ECOSYSTEM:introduced=0,fixed=2.9.0.

Q: Is there a fix for CVE-2026-31899?

Yes. CairoSVG (PyPI): upgrade to 2.9.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-31899 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-31899?

Check whether you run CairoSVG (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-2026-31899 · Severity: high · CVSS 7.5 · Published 2026-03-13

CairoSVG is a popular library used to convert SVG files into other formats like PNG or PDF. A vulnerability allows an attacker to provide a specially crafted, small SVG file that causes the system to consume 100% of its CPU resources indefinitely. This can lead to a complete service outage for any application that processes user-provided images, such as profile picture uploaders or document generators.

Technologies: CairoSVG (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-31899 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-31899 being exploited in the wild.
How severe is CVE-2026-31899?: High severity, with a CVSS score of 7.5, published 13 March 2026.
Which products and versions are affected?: CairoSVG (PyPI) <= 2.8.2, ECOSYSTEM:introduced=0,fixed=2.9.0.
Is there a fix for CVE-2026-31899?: Yes. CairoSVG (PyPI): upgrade to 2.9.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-31899 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-31899?: Check whether you run CairoSVG (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

CairoSVG (PyPI): upgrade to 2.9.0 or later
```
pip install "CairoSVG>=2.9.0"
```

Technical details

The vulnerability exists in the `use()` function within `cairosvg/defs.py`. The component fails to implement recursion depth limits or element budget constraints when processing SVG `<use>` elements. An attacker can craft a nested SVG structure where each level references the previous one multiple times, leading to O(10^N) rendering calls from a small input (e.g., a 1.4KB file). This results in indefinite CPU exhaustion without triggering Out-of-Memory (OOM) killers, as memory usage remains relatively flat. The issue is fixed in version 2.9.0.

Affected products

Kozea CairoSVG <= 2.8.2

Identifiers

CVE-2026-31899
GHSA-f38f-5xpm-9r7c
PYSEC-2026-2122

Timeline

2026-03-13: disclosed
2026-03-13: advisory
2026-03-13: patched: Fixed in version 2.9.0

References

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