CVE-2026-126064sparklemotion nokogiri use after free
CVE-2026-126064 is a use after free in sparklemotion nokogiri, rated low (2.0 on CVSS 4.0).
Why this priority: Low severity, with no exploitation signal.
Published · Updated · NVD status: Received
What it is
Code keeps using memory after releasing it, so an attacker who refills that memory can steer execution.
How it is reached
An attacker can exploit it by someone who can already run code or sign in on the machine, with an ordinary user account, and nobody has to click anything. Success also depends on conditions the attacker does not fully control.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker crash the process, read memory, or in the worst case run code.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- Upgrade sparklemotion nokogiri to 1.19.5 or later.
- Limit who can run code or sign in on the hosts that run it.
Description from NVD
Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.5, the CRuby native extension can leave Ruby wrappers pointing to freed memory when Nokogiri::XML::Node#[]= or Nokogiri::XML::Node#lang= replaces an existing attribute value after code has accessed the attribute's child nodes. Replacing the value frees native child nodes while their wrappers remain reachable, and later use of those wrappers can cause an invalid read or process segfault. JRuby is not affected. This issue is fixed in version 1.19.5.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Native code: operating systems, browsers and firmware. The flaw sits wherever native code reads untrusted data.
- Network appliances and media or file parsers. The flaw sits wherever native code reads untrusted data.
Trust boundaries in play
- Host boundary. The attacker needs a foothold on the machine first; the flaw turns a small foothold into a bigger one.
- Wherever native code reads untrusted data. An attacker who crosses it can crash the process, read memory, or in the worst case run code.
Questions to answer about your own systems
- Where does sparklemotion nokogiri run in your systems, and at which version?
- Which of those hosts also run code or users you do not fully trust?
- What can it reach once compromised: which data stores, secrets and services?
Read more
Patches and commits
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.