ZDI-26-426: OpenSSL X.509 Email Validation Out-Of-Bounds Read Information Disclosure Vulnerability
This vulnerability allows remote attackers to disclose sensitive information on affected installations of OpenSSL. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 6.5. The following CVEs are assigned: CVE-2026-42771.
AI Analysis
Technical Summary
CVE-2026-42771 is an information disclosure vulnerability in OpenSSL affecting the processing of X.509 email names. Due to insufficient validation of user-supplied data, an out-of-bounds read can occur, allowing remote attackers to disclose sensitive information in the context of the service account. Exploitation does not require authentication. OpenSSL has issued a patch to fix this vulnerability.
Potential Impact
Remote attackers can exploit this vulnerability to disclose sensitive information from the affected OpenSSL installation without needing authentication. The disclosed information is accessible in the context of the service account running OpenSSL. There is no indication of integrity or availability impact beyond information disclosure.
Mitigation Recommendations
OpenSSL has issued an official update that corrects this vulnerability. Users and administrators should apply the OpenSSL update as soon as possible to remediate this issue.
ZDI-26-426: OpenSSL X.509 Email Validation Out-Of-Bounds Read Information Disclosure Vulnerability
Description
This vulnerability allows remote attackers to disclose sensitive information on affected installations of OpenSSL. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 6.5. The following CVEs are assigned: CVE-2026-42771.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-42771 is an information disclosure vulnerability in OpenSSL affecting the processing of X.509 email names. Due to insufficient validation of user-supplied data, an out-of-bounds read can occur, allowing remote attackers to disclose sensitive information in the context of the service account. Exploitation does not require authentication. OpenSSL has issued a patch to fix this vulnerability.
Potential Impact
Remote attackers can exploit this vulnerability to disclose sensitive information from the affected OpenSSL installation without needing authentication. The disclosed information is accessible in the context of the service account running OpenSSL. There is no indication of integrity or availability impact beyond information disclosure.
Mitigation Recommendations
OpenSSL has issued an official update that corrects this vulnerability. Users and administrators should apply the OpenSSL update as soon as possible to remediate this issue.
Technical Details
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-426/","fetched":true,"fetchedAt":"2026-07-16T15:51:02.705Z","wordCount":198}
Threat ID: 6a58fe6668715ace43485bf0
Added to database: 07/16/2026, 15:53:10 UTC
Last enriched: 07/16/2026, 15:55:35 UTC
Last updated: 07/16/2026, 19:48:22 UTC
Views: 4
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