CVE-2026-9390
Xml::sig vulnerability
- Published3 Aug 2026
Description
XML::Sig versions before 0.71 for Perl allow XPath injection in ID lookup. verify() and _get_signed_xml() in lib/XML/Sig.pm build XPath expressions by concatenating the SignedInfo/Reference/@URI value read from the document being verified. The value is neither escaped nor checked against the NCName grammar that XML requires of an ID, so a URI containing a single quote closes the string literal in the generated expression and appends arbitrary XPath operators. A crafted URI can make the lookup match elements the reference does not name, or every element in the document, so which node is selected for digest verification is decided by the injected expression rather than by the reference.
CVSS 3.1 breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NAffected products
Remediation
References
Related CVEs
Recent high-severity vulnerabilities sharing a weakness type.
Frequently asked
Is CVE-2026-9390 being actively exploited?
CVE-2026-9390 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.51%.
How severe is CVE-2026-9390?
CVE-2026-9390 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.51% probability of exploitation.
Which products are affected by CVE-2026-9390?
Affected products include Xml::sig.
How do I fix CVE-2026-9390?
Upgrade affected software to a fixed version, for example Xml::sig 0.71 or later, then confirm no affected versions remain in your inventory.
How Secuno handles this
Secuno correlates vulnerabilities like CVE-2026-9390 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.
Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.