Editor crash via invalid completion buffer access
Published Sep 4, 2023 · Updated Nov 3, 2025
Use-after-free in Vim before 9.0.1858 allows attackers to crash the editor when a local user runs a crafted Vim script. In ins_compl_get_exp(), a tagfunc callback can wipe the completion buffer, but the function subsequently sets b_scanned through the stale st.ins_buf pointer without confirming that the buffer remains valid. The upstream reproducer invokes insert completion from a script, so exploitation requires execution of attacker-controlled Vim commands and interrupts only that Vim process in the demonstrated case.
Summary
What happened
Use-after-free in Vim before 9.0.1858 allows attackers to crash the editor when a local user runs a crafted Vim script. In ins_compl_get_exp(), a tagfunc callback can wipe the completion buffer, but the function subsequently sets b_scanned through the stale st.ins_buf pointer without confirming that the buffer remains valid. The upstream reproducer invokes insert completion from a script, so exploitation requires execution of attacker-controlled Vim commands and interrupts only that Vim process in the demonstrated case.
The record
- CVE
- CVE-2023-4752
- Published
- Sep 4, 2023
- Updated
- Nov 3, 2025
- Vendor
- Vim
- Product
- Vim
- Classifications
- CWE-416, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 4, 2023CVE publishedPublication date reported by the CVE source.
- Nov 3, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=unspecified <9.0.1858
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Upstream poc_tagfunc.vim crash reproducerproof of concept · validated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo