CVE-2026-18839

lowCVSS 2.2covered by 2 sourcesfirst seen 2026-08-05

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.

CSIRTS triage

What: A size_t underflow in singleoptionhelp causes a memory corruption defect.
Who is affected: Users of popt-devel and popt-static libraries.
Urgency: Low severity with CVSS 2.2; no active exploitation reported.
Action: Update to a patched version of popt when available.

AI-assisted analysis generated from the source advisory — verify against the original.

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Exploitation outlook

Low exploitation risk0.08% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 0% of all EPSS-scored CVEs.

Advisory coverage (2)

lowCVE-2026-18839: Popt-devel: popt-static: size_t underflow in singleoptionhelpmsrc · 2026-08-11
lowCVE-2026-18839: An integer underflow was found in the popt library when formatting help text for option tables…nvd · 2026-08-05

External references

NVD record for CVE-2026-18839

CVE.org record

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