Deploy autonomous AI agents that reason, exploit, and validate complex vulnerability chains — not another scanner, an agentic system that thinks like a senior pentester.
CVE-2026-28386 is a high severity vulnerability with a CVSS score of 7.5. No known exploits currently, and patches are available.
Very low probability of exploitation
EPSS predicts the probability of exploitation in the next 30 days based on real-world threat data, complementing CVSS severity scores with actual risk assessment.
Issue summary: Applications using AES-CFB128 encryption or decryption on systems with AVX-512 and VAES support can trigger an out-of-bounds read of up to 15 bytes when processing partial cipher blocks.
Impact summary: This out-of-bounds read may trigger a crash which leads to Denial of Service for an application if the input buffer ends at a memory page boundary and the following page is unmapped. There is no information disclosure as the over-read bytes are not written to output.
The vulnerable code path is only reached when processing partial blocks (when a previous call left an incomplete block and the current call provides fewer bytes than needed to complete it). Additionally, the input buffer must be positioned at a page boundary with the following page unmapped. CFB mode is not used in TLS/DTLS protocols, which use CBC, GCM, CCM, or ChaCha20-Poly1305 instead. For these reasons the issue was assessed as Low severity according to our Security Policy.
Only x86-64 systems with AVX-512 and VAES instruction support are affected. Other architectures and systems without VAES support use different code paths that are not affected.
OpenSSL FIPS module in 3.6 version is affected by this issue.
| Vendor | Product |
|---|---|
| OpenSSL | OpenSSL |
Please cite this page when referencing data from Strobes VI. Proper attribution helps support our vulnerability intelligence research.