HIGH

CVE-2026-18220

Binutils: binutils: out-of-bounds write in bfd dlx elf backend relocation processing

CVSS v3

7.8

HIGH

EPSS Score

exploit probability

CISA KEV

No

known exploited

Exploitation

none

SSVC status

Description

An out-of-bounds write vulnerability was found in the BFD library's DLX ELF backend (bfd/elf32-dlx.c) in GNU binutils. The dlx_rtype_to_howto() function maps ELF relocation types to internal howto structures but fails to perform adequate bounds checking on attacker-controlled relocation type values (via ELF32_R_TYPE(r_info)) before indexing into the dlx_elf_howto_table[] array. The DLX relocation type number space is non-contiguous (basic types 0-6, extended types at 0x10000+), but the default c

Technical details

CVSS v3 Vector
3.1
Published
7/29/2026
Last Modified
7/29/2026

Frequently asked questions

What is CVE-2026-18220?

An out-of-bounds write vulnerability was found in the BFD library's DLX ELF backend (bfd/elf32-dlx.c) in GNU binutils. The dlx_rtype_to_howto() function maps ELF relocation types to internal howto structures but fails to perform adequate bounds checking on attacker-controlled relocation type values (via ELF32_R_TYPE(r_info)) before indexing into the dlx_elf_howto_table[] array. The DLX relocation type number space is non-contiguous (basic types 0-6, extended types at 0x10000+), but the default c

Is CVE-2026-18220 actively exploited?

Active exploitation of CVE-2026-18220 has not been confirmed. The EPSS score is N/A%, indicating the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-18220?

CVE-2026-18220 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string 3.1.

Is CVE-2026-18220 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.