CVE-2026-59859
Kiota PHP generator allows attacker-controlled PHP code injection into generated clients.
Is CVE-2026-59859 being exploited?
Not confirmed. CVE-2026-59859 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 1.4% probability of exploitation in the next 30 days.
How severe is CVE-2026-59859?
CVE-2026-59859 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-59859?
Yes. A fix has been recorded for CVE-2026-59859. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-59859 affect?
CVE-2026-59859 affects Kiota PHP generator < 1.32.4, Generated PHP model classes, Generated PHP request-builder classes. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-59859?
Upgrade to Kiota 1.32.4+, regenerate PHP clients, and audit generated code
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Arbitrary PHP code execution in applications that use Kiota-generated models/request-builders via unescaped $ interpolation from OpenAPI strings.
Patch when possible
- affected>= 1.30.0 and < 1.31.1
- affected< 1.29.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.