GHSA-2hfw-w739-p7x5: Duplicate Advisory: nano-id reduced entropy due to inadequate character set usage
This advisory was withdrawn on Feb 2, 2026. The publisher no longer considers it a valid vulnerability.
Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-9hc7-6w9r-wj94. This link is maintained to preserve external references. Original Description Description Affected versions of the nano-id crate incorrectly generated IDs using a reduced character set in the nanoid::base62 and nanoid::base58 functions.
Published Jun 4, 2024 · Updated Feb 2, 2026
Affected packages
nano-id
- Ecosystem
- Rust (crates.io)
- Affected
- < 0.4.0
- Fixed in
- 0.4.0
- Check
cargo tree -i nano-id
Advisory details
From the GitHub Advisory Database (CC BY 4.0).
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-9hc7-6w9r-wj94. This link is maintained to preserve external references.
Original Description
Description
Affected versions of the nano-id crate incorrectly generated IDs using a reduced character set in the nano_id::base62 and nano_id::base58 functions. Specifically, the base62 function used a character set of 32 symbols instead of the intended 62 symbols, and the base58 function used a character set of 16 symbols instead of the intended 58 symbols. Additionally, the nano_id::gen macro is also affected when a custom character set that is not a power of 2 in size is specified.
It should be noted that nano_id::base64 is not affected by this vulnerability.
Impact
This can result in a significant reduction in entropy, making the generated IDs predictable and vulnerable to brute-force attacks when the IDs are used in security-sensitive contexts such as session tokens or unique identifiers.
Patches
The flaws were corrected in commit a9022772b2f1ce38929b5b81eccc670ac9d3ab23 by updating the the nano_id::gen macro to use all specified characters correctly.
PoC
use std::collections::BTreeSet;
fn main() {
test_base58();
test_base62();
}
fn test_base58() {
let mut produced_symbols = BTreeSet::new();
for _ in 0..100_000 {
id = "RUSTSEC-2024-0343"
for c in id.chars() {
produced_symbols.insert(c);
}
}
println!(
"{} symbols generated from nano_id::base58",
produced_symbols.len()
);
}
fn test_base62() {
let mut produced_symbols = BTreeSet::new();
for _ in 0..100_000 {
id = "RUSTSEC-2024-0343"
for c in id.chars() {
produced_symbols.insert(c);
}
}
println!(
"{} symbols generated from nano_id::base62",
produced_symbols.len()
);
}References
How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology
