How severe is CVE-2026-87986?

CVE-2026-87986 has a CVSS 4.0 base score of 10.0, rated critical severity.

Is CVE-2026-87986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-87986?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-87986 published?

CVE-2026-87986 was published on 2026-09-11.

CVE-2026-87986

CVE-2026-87986 is a critical-severity vulnerability with a CVSS 4.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-228.

Key facts

Severity: Critical (CVSS 4.0 base score 10.0)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-228
Published: 2026-09-11
Last modified: 2026-09-11

Description

An arbitrary code execution vulnerability in Mistral Vibe allows an attacker to bypass command permission checks using shell constructs it's parser cannot interpret. Unparsed portions are omitted from inspection, enabling embedded commands to execute on the user's system without approval.

Frequently asked questions

What is CVE-2026-87986?: An arbitrary code execution vulnerability in Mistral Vibe allows an attacker to bypass command permission checks using shell constructs it's parser cannot interpret. Unparsed portions are omitted from inspection, enabling embedded commands to execute on the user's system without approval.
How severe is CVE-2026-87986?: CVE-2026-87986 has a CVSS 4.0 base score of 10.0, rated critical severity.
Is CVE-2026-87986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-87986?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-87986 published?: CVE-2026-87986 was published on 2026-09-11.

References

https://www.hiddenlayer.com/sai-security-advisory/2026-09-mistral-vibe4

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