CairoSVG: Inefficient Algorithmic Complexity
CVE-2026-107378 is a high-severity inefficient algorithmic complexity vulnerability in CairoSVG from Kozea, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected CairoSVG versions: < 2.9.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of CairoSVG you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Attack requirements
- NoneThe attack does not depend on a particular deployment or configuration.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- NoneNo loss of confidentiality on the vulnerable system.
- Integrity (vulnerable system)
- NoneNo loss of integrity on the vulnerable system.
- Availability (vulnerable system)
- HighSerious loss of availability on the vulnerable system.
- Confidentiality (other systems)
- NoneNo loss of confidentiality on systems beyond the vulnerable one.
- Integrity (other systems)
- NoneNo loss of integrity on systems beyond the vulnerable one.
- Availability (other systems)
- NoneNo loss of availability on systems beyond the vulnerable one.
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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. Scored by CNA (github.com).
Official description
CairoSVG is an SVG converter based on Cairo, a 2D graphics library. Prior to 2.9.1, rendering an attacker-controlled SVG with a path containing many segments can cause quadratic CPU consumption in cairosvg/path.py. The path tokenizer repeatedly slices and rescans the remaining path data, while draw_markers drains node.vertices with node.vertices.pop(0), causing repeated linear-time work. The svg2png, svg2pdf, and svg2ps APIs reach these operations during ordinary rendering, allowing a sub-megabyte SVG to consume substantial CPU and deny service to a rendering application. This issue is fixed in version 2.9.1.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Inefficient Algorithmic Complexity
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
More Inefficient Algorithmic Complexity vulnerabilities (CWE-407)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
References
Patches and release notes
Other vulnerabilities in CairoSVG
- 7.5 High severity
- 7.1 High severity
Recent Inefficient Algorithmic Complexity vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.2 High severity
- 8.7 High severity
- 8.2 High severity
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