CVE-2026-59860

HIGH 8.7 PoC AVAILABLE

Published 2026-07-16 · Last modified 2026-07-17

Kiota is an OpenAPI based HTTP Client code generator. Prior to 1.32.3, Kiota is affected by a code-generation injection vulnerability in the C# XML documentation-comment sink (the description, externalDocs label, and externalDocs link fields emitted as /// … comments). When text from an OpenAPI description is written into single-line XML doc comments without stripping newline and Unicode line-terminator characters, an attacker can break out of the /// comment line and inject additional code into generated C# clients. This issue is fixed in version 1.32.3.

EXPLOIT AVAILABLE

Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.

Exploitation likelihood

1.0%chance of exploitation in 30 days · 60th percentile

○ In CISA KEV ● Public exploit / PoC

Impact if exploited

8.7CVSS 4.0 · HIGH

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
✓Privileges: No account or privileges required
⚠User interaction: Succeeds with passive user activity
✓Complexity: No special conditions — reliably repeatable
✓Requirements: No special attack requirements

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

reference https://github.com/microsoft/kiota/security/advisories/GHSA-3hrf-2gc2-mx32
github-search Search GitHub for public PoC repos

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-59860/poc.jsonMachine-readable PoC index for this CVE (for automation).

Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-59860/poc.json

Affected

Vendors Microsoft

Products Kiota

Weakness (CWE)

CWE-94: : Improper Control of Generation of Code ('Code Injection')

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

All CVSS metrics

HIGH 8.7 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
HIGH 8.7 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/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

References

Exploits & PoC

https://github.com/microsoft/kiota/security/advisories/GHSA-3hrf-2gc2-mx32 x_refsource_CONFIRMexploit

Technical & other

https://github.com/microsoft/kiota/pull/7831 x_refsource_MISC
https://github.com/microsoft/kiota/commit/ebb632db90aa8e3c20949337d9faa2720d64ca44 x_refsource_MISC
https://github.com/microsoft/kiota/releases/tag/v1.32.3 x_refsource_MISC

Sources: NVD · CVE.org · EPSS