CVE-2026-66360: Out-of-bounds Read (CVSS 7.5)

Description

The ISO Presentation layer contains a flaw in the handling of specific parameters during normal mode negotiation. A missing length check in the processing of the encoded presentation data allows an attacker controlled field with a zero length value to trigger a bounded heap over read. This condition occurs before MMS session establishment, a crafted TCP/102 connection attempt can trigger the issue. The resulting over read causes the process to terminate, leading to a denial of service condition.

Is your site exposed to CVE-2026-66360?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0028

Probability of exploitation

0.20%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

References

Other References

https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-10.json https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-10

Frequently Asked Questions

What is CVE-2026-66360? +

The ISO Presentation layer contains a flaw in the handling of specific parameters during normal mode negotiation. A missing length check in the processing of the encoded presentation data allows an attacker controlled field with a zero length value to trigger a bounded heap over read. This condition occurs before MMS session establishment, a crafted TCP/102 connection attempt can trigger the issue. The resulting over read causes the process to terminate, leading to a denial of service condition. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-66360? +

CVE-2026-66360 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0028, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-66360? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-29013

libcoap contains out-of-bounds read vulnerabilities in OSCORE Appendix B.2 CBOR unwrap handling where get_byte_inc() in src/oscore/oscore_cbor.c relies solely on assert() …

CVE-2026-53566

Out-of-bounds read vulnerability in Citrix Citrix Secure Access Client for Windows. This issue affects Citrix Secure Access Client for Windows: …

CVE-2026-3508

An Out-of-bounds Read vulnerability in the IOCTL handler in ASUS System Control Interface allows a local user to cause system …

CVE-2025-48520

An improper input validation vulnerability within the AMD Platform Management Framework (PMF) driver can allow a local attacker to read …

CVE-2026-3894

Out-of-bounds Read vulnerability in RTI Connext Professional (Core Libraries) allows Overread Buffers.This issue affects Connext Professional: from 7.4.0 before 7.7.0, …

CVE-2025-4098

Horner Automation Cscape version 10.0 (10.0.415.2) SP1 is vulnerable to an out-of-bounds read vulnerability that could allow an attacker to …

CVE-2026-66360