Vim 9.2.0670 Buffer Overread via get_text_props() in Undo File
CVE-2026-57451 Published on June 25, 2026
Vim: Out-of-bounds Read in Text Property Count
Vim is an open source, command line text editor. Prior to 9.2.0670, get_text_props() in src/textprop.c reads a uint16 property count stored inline after a line's text and returns it as the number of 32-byte textprop_T entries that follow. The only check is a floor that guarantees room for a single entry; the count is never checked against the amount of data actually present. A line that declares a large count while carrying little data causes consumers to read far past the end of the line buffer. Such a line can be delivered through a crafted undo file, leading to a crash. This vulnerability is fixed in 9.2.0670.
Vulnerability Analysis
CVE-2026-57451 can be exploited with local system access, requires user interaction. This vulnerability is consided to have a high level of attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity, and a high impact on availability.
Weakness Type
Out-of-bounds Read
The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.
Products Associated with CVE-2026-57451
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