CVE-2026-40296

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.22% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 13.0% of scored records. A rank, not a probability.

NVD base score

5.4 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Analyzed. NVD last modified this record on 2026-10-26.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-05-06 20:48Z5 MO AGO

Last updated

2026-05-07 14:03Z5 MO AGO

Reserved

2026-04-10

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Medium (CVSS 5.4)

CNA CVSS vector

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

Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base

Data version

5.2

Document digest

b3079dca842d9711d935921d2fd13ba3ddbd1bca4bc0abafada6252e0c9d5bc7

• github.comhttps://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-hrmw-qprp-wgmcx_refsource_CONFIRM