CVE-2025-26603

MEDIUMCVSS 4.2/10EPSS 0.22%

Last modified

CVE-2025-26603 is a medium-severity vulnerability rated 4.2/10 on the CVSS scale. Vim is a greatly improved version of the good old UNIX editor Vi. Vim allows to redirect screen messages using the `:redir` ex command to register, variables and files. EPSS estimates a 0.22% chance of exploitation in the next 30 days.

Description

Vim is a greatly improved version of the good old UNIX editor Vi. Vim allows to redirect screen messages using the `:redir` ex command to register, variables and files. It also allows to show the contents of registers using the `:registers` or `:display` ex command. When redirecting the output of `:display` to a register, Vim will free the register content before storing the new content in the register. Now when redirecting the `:display` command to a register that is being displayed, Vim will free the content while shortly afterwards trying to access it, which leads to a use-after-free. Vim pre 9.1.1115 checks in the ex_display() function, that it does not try to redirect to a register while displaying this register at the same time. However this check is not complete, and so Vim does not check the `+` and `*` registers (which typically donate the X11/clipboard registers, and when a clipboard connection is not possible will fall back to use register 0 instead. In Patch 9.1.1115 Vim will therefore skip outputting to register zero when trying to redirect to the clipboard registers `*` or `+`. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Metrics

CVSS 3.1
4.2/10

CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L

EPSS Probability
0.22%

13.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
VimVim< 9.1.1115
NetappHci Compute NodeAll versions

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2025-26603?
Vim is a greatly improved version of the good old UNIX editor Vi. Vim allows to redirect screen messages using the `:redir` ex command to register, variables and files. It also allows to show the contents of registers using the `:registers` or `:display` ex command. When redirecting the output of `:display` to a register, Vim will free the register content before storing the new content in the register. Now when redirecting the `:display` command to a register that is being displayed, Vim will free the content while shortly afterwards trying to access it, which leads to a use-after-free. Vim pre 9.1.1115 checks in the ex_display() function, that it does not try to redirect to a register while displaying this register at the same time. However this check is not complete, and so Vim does not check the `+` and `*` registers (which typically donate the X11/clipboard registers, and when a clipboard connection is not possible will fall back to use register 0 instead. In Patch 9.1.1115 Vim will therefore skip outputting to register zero when trying to redirect to the clipboard registers `*` or `+`. Users are advised to upgrade. There are no known workarounds for this vulnerability.
How severe is CVE-2025-26603?
CVE-2025-26603 has a CVSS score of 4.2/10 (MEDIUM severity). The EPSS model estimates a 0.22% probability of exploitation in the next 30 days.
How do I fix CVE-2025-26603?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-26603?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST