CVE-2026-43888

High
8.7
0.05.010.0
Year
2026
Published
May 11, 2026
Known Affected Devices
0
CVSS Score
8.7

What is CVE-2026-43888?

Outline is a service that allows for collaborative documentation. Prior to 1.7.0, ZipHelper.extract computes the extraction path for each entry by passing a full filesystem path through trimFileAndExt, a filename helper that calls path.basename on its input when truncating. When a zip entry's nested path is long enough to push the joined filesystem path over MAX_PATH_LENGTH (4096 bytes), trimFileAndExt silently drops all directory components and returns a bare filename. fs.createWriteStream then opens the file relative to the process working directory instead of inside the extraction sandbox, and the escaped file persists after import cleanup because cleanupExtractedData only removes the temporary extraction directory. This vulnerability is fixed in 1.7.0.

CVSS Vector Breakdown

CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:H
AV
Attack Vector
Network

Exploitable remotely over the network without requiring access to the local system.

AC
Attack Complexity
Low

No special conditions required. Exploit can be performed reliably and repeatedly.

PR
Privileges Required
High

Administrative or root-level privileges required to exploit.

UI
User Interaction
None

No user interaction required. Exploit runs without any victim action.

S
Scope
Changed

Exploiting the vulnerability can affect other components beyond the vulnerable one.

C
Confidentiality Impact
None

No confidentiality impact. Sensitive data is not exposed.

I
Integrity Impact
High

Complete loss of integrity. Attacker can modify any file or data on the component.

A
Availability Impact
High

Complete denial of service. The component becomes fully unavailable.

FAQ

How severe is CVE-2026-43888?

CVE-2026-43888 has a CVSS score of 8.7/10, rated as High. This is a high severity vulnerability and should be patched as soon as possible.

What does the CVSS score mean for CVE-2026-43888?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-43888 scores 8.7/10 (High). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.

Which devices are affected by CVE-2026-43888?

The list of devices confirmed to be affected by CVE-2026-43888 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.

How do I fix or mitigate CVE-2026-43888?

Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.