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+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "memmap2"
+date = "2026-06-20"
+url = "https://github.com/RazrFalcon/memmap2-rs/issues/169"
+references = ["https://github.com/RazrFalcon/memmap2-rs/pull/170"]
+informational = "unsound"
+keywords = ["pointer-arithmetic", "out-of-bounds"]
+
+[affected.functions]
+"memmap2::Mmap::advise_range" = [">= 0.5.9","< 0.9.11"]
+"memmap2::Mmap::unchecked_advise_range" = [">= 0.8.0","< 0.9.11"]
+"memmap2::MmapMut::advise_range" = [">= 0.5.9","< 0.9.11"]
+"memmap2::MmapMut::flush_async_range" = ["< 0.9.11"]
+"memmap2::MmapMut::flush_range" = ["< 0.9.11"]
+"memmap2::MmapMut::unchecked_advise_range" = [">= 0.8.0","< 0.9.11"]
+
+[versions]
+patched = [">= 0.9.11"]
+```
+
+# Unchecked pointer offset in crate `memmap2`
+
+Affected versionf of `memmap2` did not perform enough validation on the `offset` and `len` parameters of
+`Mmap::[unchecked_]advise_range()`,
+`MmapMut::[unchecked_]advise_ranage()`
+and `MmapMut::flush[_async]_range()`.
+
+This can cause undefined behavior due to invalid values being passed to [`pointer::offset()`] and [`pointer::add()`]
+when passing an out-of-bounds range to any of the affected functions.
+
+The flaw was corrected in commit [`cee7cf0`] and released in version `0.9.11`.
+
+The invalid pointer is not dereferenced,
+but it is passed to the `madvise` and `msync` syscalls and their Windows equivalents.
+
+[`pointer::offset()`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.offset-1
+[`pointer::add()`]: https://doc.rust-lang.org/stable/std/primitive.pointer.html#method.add-1
+[`cee7cf0`] https://github.com/RazrFalcon/memmap2-rs/pull/170/changes/cee7cf03a9ee095982a3c37b7aac8e3f68f1a00c