How severe is CVE-2026-86189?

CVE-2026-86189 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-86189 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-86189?

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-2026-86189 published?

CVE-2026-86189 was published on 2026-09-05 and last updated on 2026-09-18.

CVE-2026-86189

CVE-2026-86189 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. 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-73.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.3
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-73
Published: 2026-09-05
Last modified: 2026-09-18

Description

WWBN AVideo contains a path traversal vulnerability in notify.ffmpeg.json.php that allows unauthenticated attackers to write files to arbitrary locations by supplying a caller-chosen path in the avideoRelativePath parameter. Attackers can replay any previously issued ciphertext as a notifyCode token, which is decrypted but never validated, to bypass authentication and write files to the application root and subdirectories.

Frequently asked questions

What is CVE-2026-86189?: WWBN AVideo contains a path traversal vulnerability in notify.ffmpeg.json.php that allows unauthenticated attackers to write files to arbitrary locations by supplying a caller-chosen path in the avideoRelativePath parameter. Attackers can replay any previously issued ciphertext as a notifyCode token, which is decrypted but never validated, to bypass authentication and write files to the application root and subdirectories.
How severe is CVE-2026-86189?: CVE-2026-86189 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-86189 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-86189?: 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-2026-86189 published?: CVE-2026-86189 was published on 2026-09-05 and last updated on 2026-09-18.

References

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