CVE-2026-58081

CriticalCVSS 9.8

Published: 19/08/2026(UTC)Updated: 31/08/2026(UTC)Translated: 19/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.36%

29th percentile - higher than 29% of all known CVEs

Summary

Several encoding modules, including HZ, UTF-7, VIQR, and ZW, did not properly check the size of the caller-supplied output buffer before writing converted characters. An application that uses iconv(3) to convert untrusted input to or from one of the affected encodings may be vulnerable to buffer overflows if it uses one of the affected encoding modules.

Risk Assessment

Applications processing untrusted data with iconv may be exploited to execute arbitrary code or cause a crash.

Recommendation

Apply the vendor patch that fixes the buffer size checks in the mentioned encoding modules.

Other vulnerabilities in FreeBSD libc

CVE-2026-58082Critical
The ISO-2022 encoding module used a stack buffer sized to MB_LEN_MAX (6 bytes) for intermediate character output. Some ISO-2022 variants can require up to 10 bytes per character, in which case conversions can trigger a stack buffer overflow of up to four bytes. An application that uses iconv(3) to convert untrusted input to or from one of the affected encodings may be vulnerable to buffer overflows if it uses one of the affected encoding modules.

Original NVD description (English source)

Vulnerability data from NVD (NIST) · CISA KEV · EPSS