Heap-based Buffer Overflow Affecting openssl package, versions [1.0.2u,3.1.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-CONAN-OPENSSL-17276655
- published10 Jun 2026
- disclosed9 Jun 2026
- creditZehua Qiao, Jinwen He
Introduced: 9 Jun 2026
NewCVE-2026-7383 (opens in a new tab)How to fix?
Upgrade openssl to version 3.1.0 or higher.
Overview
Affected versions of this package are vulnerable to Heap-based Buffer Overflow in ASN1_mbstring_ncopy() and ASN1_mbstring_copy(). An attacker supplying input on the order of 2^30 characters can overflow the signed int destination size computation for Unicode output, wrapping the allocation size to zero and causing the character copy to write gigabytes past a one-byte buffer, leading to a crash or possibly code execution. No OpenSSL network or certificate-handling path reaches the overflow; triggering it requires an application to call these functions directly, or to register a custom string type via ASN1_STRING_TABLE_add(), with attacker-controlled input of at least half a gigabyte.