CVE-2026-58082: freebsd Stack-based Buffer Overflow

Vulnerability summary

CVE-2026-58082 is a critical (CVSS 9.8) Stack-based Buffer Overflow vulnerability in freebsd. EPSS estimates a 0.52% chance of exploitation in the next 30 days, higher than 42.8% of scored vulnerabilities.

Timeline

1. 19-08-2026
   PublishedVulnerability first disclosed.
2. 26-08-2026
   Last modifiedVulnerability information updated.

Description

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.

• CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).