CVE-2026-18743 (CVSS 2.5)

Description

A flaw was found in popt. This vulnerability allows an attacker to provide specially crafted configuration content to a host, which, when loaded, can lead to a small memory corruption issue. This occurs because of an error in how the `poptConfigFileToString` function reallocates memory for buffers. Successful exploitation could result in heap metadata corruption, potentially causing the affected process to become unavailable (denial of service).

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CVSS v3.1 Score

2.5

LOW

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

EPSS — Exploit Prediction

0.0014

Probability of exploitation

0.04%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-131 CWE-131

References

Other References

https://access.redhat.com/security/cve/CVE-2026-18743 https://bugzilla.redhat.com/show_bug.cgi?id=2510809

Frequently Asked Questions

What is CVE-2026-18743? +

A flaw was found in popt. This vulnerability allows an attacker to provide specially crafted configuration content to a host, which, when loaded, can lead to a small memory corruption issue. This occurs because of an error in how the `poptConfigFileToString` function reallocates memory for buffers. Successful exploitation could result in heap metadata corruption, potentially causing the affected process to become unavailable (denial of service). It has a CVSS v3.1 base score of 2.5 (LOW).

How severe is CVE-2026-18743? +

CVE-2026-18743 has a CVSS v3.1 score of 2.5 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0014, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-18743? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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