CVE-2026-55948
Status: AnalyzedHigh (7.8)—
Use after free in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Base score: 7.8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.47%
- Percentile among all scored CVEs: 38
- Score date: 10/4/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
🎯 ATT&CK techniques
How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.
- Exploitation
T1203Exploitation for Client Executionexecution90 % - Primary impact
T1059Command and Scripting Interpreterexecution85 %
CWE-416 (use-after-free) en Excel con UI:R permite ejecución de código al abrir un archivo preparado, característica de explotación en cliente (T1203). El impacto es ejecución de comandos (T1059).
Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.
🛡️ ATT&CK mitigations that cover these techniques
Affected technologies (7)
CWEs
- CWE-416
References
Raw JSON (NVD)
Show
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