CVE-2026-32253

CRITICAL
Published May 22, 2026 Modified May 26, 2026 CWE-287 CWE-295

Description

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.

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0003
Probability of exploitation
0.10%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-287 Improper Authentication
CWE-295 CWE-295

Affected Products

Vendor Product
lizardbyte sunshine

References

Frequently Asked Questions

What is CVE-2026-32253? +
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. It has a CVSS v3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2026-32253? +
CVE-2026-32253 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0003, placing it in the 0th percentile for exploitation probability.
What products are affected by CVE-2026-32253? +
CVE-2026-32253 affects products from lizardbyte, specifically: sunshine. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2026-32253? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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