# CVE-2026-5295 — wolfSSL

> As of 2026-04-14, CVE-2026-5295 is a Medium-severity (band derived from the CVSS v4.0 score, not stated by the CNA) vulnerability in wolfSSL, CVSS v4.0 5.9, EPSS 0.2% (18.0th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-5295, most recently “Multiple WolfSSL Critical Vulnerabilities: Certificate Bypass, RCE, and Post-Quantum Weakening”.

**Last updated:** 2026-04-14

## What is CVE-2026-5295?

A stack buffer overflow exists in wolfSSL's PKCS7 implementation in the wc_PKCS7_DecryptOri() function in wolfcrypt/src/pkcs7.c. When processing a CMS EnvelopedData message containing an OtherRecipientInfo (ORI) recipient, the function copies an ASN.1-parsed OID into a fixed 32-byte stack buffer (oriOID[MAX_OID_SZ]) via XMEMCPY without first validating that the parsed OID length does not exceed MAX_OID_SZ. A crafted CMS EnvelopedData message with an ORI recipient containing an OID longer than 32 bytes triggers a stack buffer overflow. Exploitation requires the library to be built with --enable-pkcs7 (disabled by default) and the application to have registered an ORI decrypt callback via wc_PKCS7_SetOriDecryptCb().

The record classifies CVE-2026-5295 under weakness class [CWE-121](https://intel.threadlinqs.com/cwe/CWE-121). 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 184 days ago.

## Severity and exploitation probability

- **CVSS v4.0 base score:** 5.9 — Medium (derived from score) (`CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N`)
- **EPSS (FIRST):** 0.2% probability of exploitation in the next 30 days, higher than 18.0% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5.7/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-04-09, last modified 2026-04-14

## Is CVE-2026-5295 being exploited?

Weaponised exploit code for CVE-2026-5295 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 18 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-5295.md) (trickest)

## Affected products and versions

- [wolfSSL](https://intel.threadlinqs.com/vendors/wolfssl): wolfSSL

## How to fix CVE-2026-5295

No vendor patch reference has been recorded for CVE-2026-5295 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-5295

1 tracked threat in the Threadlinqs corpus references CVE-2026-5295, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple WolfSSL Critical Vulnerabilities: Certificate Bypass, RCE, and Post-Quantum Weakening](https://intel.threadlinqs.com/threat/TL-2026-1008) — CRITICAL · 2026-06-30

## Sources

Enriched from CVE.org, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [github.com](https://github.com/wolfSSL/wolfssl/pull/10116)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-5295
Full detection coverage and IOCs for threats exploiting CVE-2026-5295 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp