CVE-2026-59859: Kiota is an OpenAPI based HTTP Client code generator

Q: How do I fix CVE-2026-59859?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Q: Is CVE-2026-59859 being exploited?

CVE-2026-59859 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-59859 affect?

CVE-2026-59859 affects affected software. Severity is high (CVSS 8.7). Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.29.1 and 1.32.4, Kiota's PHP generator embedded OpenAPI description, default fields, property names, and other schema-derived strings into PHP double-quoted literals through S

This month

HIGH 8.7

CVE-2026-59859 is a high-severity flaw (CVSS 8.7) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.29.1 and 1.32.4, Kiota's PHP generator embedded OpenAPI description, default fields, property names, and other schema-derived strings into PHP double-quoted literals through SanitizeDoubleQuote() in Writers/StringExtensions.cs without escaping $, allowing attacker-controlled ${...}, $var, or {$obj->prop} interpolation constructs to inject arbitrary PHP code into generated model and

Why this priority

High severity

A fixed release or distro patch exists.

Risk facts

CVSS score	8.7 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Passive
EPSS exploit chance	1.4% (top 28%)
CISA exploited list	No
Weakness	CWE-94
Published	2026-07-16
Last modified	2026-10-24

Publisher (CNA): GitHub, Inc.

Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Timeline

2026-07-16 15:16 UTCPublished CVE record published
2026-10-24 21:10 UTCUpdated Record last modified

Exact fixes by distribution

NuGet (.NET) · Microsoft.OpenApi.Kiota · FIXED · 1.32.4 · vulnerable: >= 1.30.0, < 1.32.4 · source

dotnet add package Microsoft.OpenApi.Kiota --version 1.32.4

NuGet (.NET) · Microsoft.OpenApi.Kiota.Builder · FIXED · 1.32.4 · vulnerable: >= 1.30.0, < 1.32.4 · source

dotnet add package Microsoft.OpenApi.Kiota.Builder --version 1.32.4

Fedora ELN · mingw-pcre2 · FIXED · 10.49-1.eln159 · FEDORA-2026-f41c1162af · source

sudo dnf upgrade --advisory=FEDORA-2026-f41c1162af

Fedora 46 · mingw-cfitsio · FIXED · 4.7.0-2.fc46 · FEDORA-2026-425e65a7c8 · source

sudo dnf upgrade --advisory=FEDORA-2026-425e65a7c8

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-59859?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Is CVE-2026-59859 being exploited?

CVE-2026-59859 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-59859 affect?

CVE-2026-59859 affects affected software. Severity is high (CVSS 8.7). Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.29.1 and 1.32.4, Kiota's PHP generator embedded OpenAPI description, default fields, property names, and other schema-derived strings into PHP double-quoted literals through S

How urgent is CVE-2026-59859?

Priority 48/100. High severity

Software pages

PHP vulnerabilities

References

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