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 related to X.509 email validation. The vulnerability occurs due to an out-of-bounds read caused by insufficient validation of user-supplied data when processing expected X.509 email names. This flaw allows remote attackers to disclose sensitive information in the context of the service account without requiring authentication. OpenSSL has issued an update to fix this vulnerability.
Potential Impact
Remote attackers can exploit this vulnerability without authentication to read memory beyond allocated buffers, potentially disclosing sensitive information accessible to the service account running OpenSSL. This could lead to leakage of confidential data but does not affect integrity or availability.
Mitigation Recommendations
OpenSSL has released an update that corrects this vulnerability. Users should apply the official OpenSSL update to remediate this issue. No other mitigations or workarounds are specified.
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 related to X.509 email validation. The vulnerability occurs due to an out-of-bounds read caused by insufficient validation of user-supplied data when processing expected X.509 email names. This flaw allows remote attackers to disclose sensitive information in the context of the service account without requiring authentication. OpenSSL has issued an update to fix this vulnerability.
Potential Impact
Remote attackers can exploit this vulnerability without authentication to read memory beyond allocated buffers, potentially disclosing sensitive information accessible to the service account running OpenSSL. This could lead to leakage of confidential data but does not affect integrity or availability.
Mitigation Recommendations
OpenSSL has released an update that corrects this vulnerability. Users should apply the official OpenSSL update to remediate this issue. No other mitigations or workarounds are specified.
Technical Details
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-426/","fetched":true,"fetchedAt":"2026-07-16T15:51:02.705Z","wordCount":198}
- Classification
- {"confidence":0.95,"severitySource":"cvss-text","classifier":"rss-v2"}
Threat ID: 6a58fe6668715ace43485bf0
Added to database: 07/16/2026, 15:53:10 UTC
Last enriched: 08/07/2026, 06:03:43 UTC
Last updated: 08/28/2026, 10:52:08 UTC
Views: 79
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