CVE-2026-32253 | Sunshine: Authentication bypass via improper client certificate validation

Exp

Sunshine is a self-hosted game stream host for Moonlight. In versions prior to 2026.516.143833, the client-certificate authentication can be bypassed because of how OpenSSL verification results are handled. In src/crypto.cpp, the custom verify callback treats X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY, X509_V_ERR_CERT_NOT_YET_VALID, and X509_V_ERR_CERT_HAS_EXPIRED as success. This can allow an untrusted certificate to pass authentication and access protected HTTPS endpoints. This issue has been fixed in version 2026.516.143833.

Published: 2026-05-22 Last update: 2026-05-26 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-32253 is rated Exploit Available (58/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.04%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-32253

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-32253

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-23 — 0.04% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-32253

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2026-32253

Affected software / configurations for CVE-2026-32253

Vendor Product Version Raw CPE
lizardbyte sunshine < 2026.516.143833 cpe:2.3:a:lizardbyte:sunshine:*:*:*:*:*:*:*:*

References for CVE-2026-32253

cvelogic Threat Intelligence