CVE-2026-4159
Out-of-Bounds Heap Read in wolfSSL PKCS7 EnvelopedData
Publication date: 2026-03-19
Last updated on: 2026-04-29
Assigner: wolfSSL Inc.
Description
Description
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| wolfssl | wolfssl | to 5.9.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-125 | The product reads data past the end, or before the beginning, of the intended buffer. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability is a 1-byte out-of-bounds (OOB) heap read in the function wc_PKCS7_DecodeEnvelopedData within wolfSSL versions 5.8.4 and earlier. It occurs when processing a specially crafted CMS EnvelopedData message that contains zero-length encrypted content. This means the software reads one byte beyond the allocated memory buffer, which can lead to unexpected behavior or information disclosure.
It is important to note that PKCS7 support is disabled by default in wolfSSL, so this vulnerability only affects systems where PKCS7 is enabled.
How can this vulnerability impact me? :
The impact of this vulnerability is relatively low, as indicated by its CVSS base score of 1.2. It involves a 1-byte out-of-bounds heap read, which could potentially lead to minor information disclosure or cause a crash. However, it requires a locally accessible attacker (AV:L) with low attack complexity and partial attack type.
Since PKCS7 support is disabled by default, the vulnerability only affects systems that have explicitly enabled this feature and process crafted CMS EnvelopedData messages with zero-length encrypted content.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
I don't know