CVE-2026-18839

Low
2.2
0.05.010.0
Year
2026
Published
Aug 5, 2026
Known Affected Devices
0
CVSS Score
2.2

What is CVE-2026-18839?

An integer underflow was found in the popt library when formatting help text for option tables that exceed the terminal width. A local user who can cause an application to print help under those conditions may cause that application to crash or fail to display help, resulting in a denial of service of the affected application.

CVSS Vector Breakdown

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

Requires local access — attacker must be logged in or have physical access to the device.

AC
Attack Complexity
High

Exploit requires specific conditions, timing, or configuration to succeed.

PR
Privileges Required
Low

Basic user account required (e.g. standard login without admin rights).

UI
User Interaction
Required

Victim must take an action (e.g. click a link, open a file) for the exploit to succeed.

S
Scope
Unchanged

Exploiting the vulnerability only affects the vulnerable component itself.

C
Confidentiality Impact
None

No confidentiality impact. Sensitive data is not exposed.

I
Integrity Impact
None

No integrity impact. Data cannot be modified.

A
Availability Impact
Low

Reduced performance or intermittent outages, but service remains available.

FAQ

How severe is CVE-2026-18839?

CVE-2026-18839 has a CVSS score of 2.2/10, rated as Low. Review the affected products list and apply vendor patches.

What does the CVSS score mean for CVE-2026-18839?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-18839 scores 2.2/10 (Low). 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-2026-18839?

The list of devices confirmed to be affected by CVE-2026-18839 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-2026-18839?

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.