CVE-2021-21974

8.8 HIGH

OpenSLP as used in ESXi (7.0 before ESXi70U1c-17325551, 6.7 before ESXi670-202102401-SG, 6.5 before ESXi650-202102101-SG) has a heap-over...

Published: 2021-02-24 · Last updated: 2026-06-02

Severity and scoring

CVSS: 8.8 HIGH
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE: CWE-787

Affected products

Vendor	Product
vmware	cloud_foundation, esxi

Description

OpenSLP as used in ESXi (7.0 before ESXi70U1c-17325551, 6.7 before ESXi670-202102401-SG, 6.5 before ESXi650-202102101-SG) has a heap-overflow vulnerability. A malicious actor residing within the same network segment as ESXi who has access to port 427 may be able to trigger the heap-overflow issue in OpenSLP service resulting in remote code execution.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-21974
[Exploit reference]http://packetstormsecurity.com/files/162957/VMware-ESXi-OpenSLP-Heap-Overflow.html
[Vendor advisory]https://www.vmware.com/security/advisories/VMSA-2021-0002.html
[Other]https://www.zerodayinitiative.com/advisories/ZDI-21-250/
[Exploit reference]http://packetstormsecurity.com/files/162957/VMware-ESXi-OpenSLP-Heap-Overflow.html
[Vendor advisory]https://www.vmware.com/security/advisories/VMSA-2021-0002.html
[Other]https://www.zerodayinitiative.com/advisories/ZDI-21-250/

Related CVEs

Same vendor

CVE-2026-41856 — The Spring GraphQL annotation detection mechanism for @Controller data fetchers may not correctly resolve annotations on methods within t... (7.5 HIGH)
CVE-2026-41700 — Spring for GraphQL applications that have enabled the WebSocket transport are vulnerable to Cross-Site WebSocket Hijacking (8.1 HIGH)
CVE-2026-41699 — Spring for GraphQL applications are vulnerable to Unsafe Deserialization when processing paginated GraphQL queries (8.1 HIGH)
CVE-2026-41694 — Since Spring Security SAML decrypts SAML Responses as well as elements of SAML LogoutRequests and LogoutResponses without requiring a val... (3.7 LOW)
CVE-2026-41003 — An attacker able to influence values in RelyingPartyRegistration may be able to run arbitrary code on HTML forms generated by Spring Secu... (7.6 HIGH)

Same CWE

CVE-2026-47750 — stable-diffusion.cpp is a pure C/C++ library for running diffusion model (Stable Diffusion, Flux, Wan, Qwen Image, Z-Image, and more) inf... (7.8 HIGH)
CVE-2026-47747 — stable-diffusion.cpp is a pure C/C++ library for running diffusion model (Stable Diffusion, Flux, Wan, Qwen Image, Z-Image, and more) inf... (7.8 HIGH)
CVE-2026-47749 — stable-diffusion.cpp is a pure C/C++ library for running diffusion model (Stable Diffusion, Flux, Wan, Qwen Image, Z-Image, and more) inf... (7.8 HIGH)
CVE-2026-12314 — Memory safety bug fixed in Thunderbird 152 (7.5 HIGH)
CVE-2026-12310 — Memory safety bug fixed in Thunderbird 152 (7.5 HIGH)