SB20261111138 - Out-of-bounds read in Vim

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds read (CVE-ID: N/A)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service by crashing Vim.

The vulnerability exists due to an out-of-bounds read in Vim's spell file processing when free_sal_items() interprets soundfolding pointers from an SN_SOFO section as salitem_T entries while loading a second SN_SOFO section. A remote attacker can trick a victim into opening a file whose modeline enables 'spell' and sets 'spelllang' to a crafted .spl file containing two SN_SOFO sections, with 'modeline' enabled, to crash Vim.

Exploitation also requires a multi-byte 'encoding', such as utf-8.

Remediation

Install update from vendor's website.

References

• https://github.com/vim/vim/security/advisories/GHSA-26qr-jvfj-hcwm
• https://github.com/vim/vim/commit/bdcb63d47fa5e86406a7b04a0ab62638018fb6b5