Answer in brief
CVE-2022-31100 records a Unknown severity vulnerability in Panic due to improper UTF-8 indexing. The current sources do not mark it as known exploited. The current feed maps rulex (crates.io). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps rulex (crates.io). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| rulexcrates.io | >=0.0.0-0 <0.4.3 | 0.4.3 |
Published upstream
May 21, 2022
Evidence: source:osv:source_dates:source-dates:recordSource modified
Oct 12, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Oct 12, 2026
When parsing untrusted rulex expressions, rulex may panic, possibly enabling a Denial of Service attack. This happens when the expression contains a multi- byte UTF-8 code point in a string literal or after a backslash, because rulex tries to slice into the code point and panics as a result. The flaw was corrected in commits `fac6d58b25` and `330b3534e7` by using `len_utf8()` to derive character width in bytes instead of assuming ASCII encoding of 1 byte per char.
Quoted source text, attributed separately from HOL analysis.