ratex-parser panics on `\verb` with a multibyte delimiter (UTF-8 byte-boundary slice) (CVE-2026-53530) | HOL Guard CVE

High · CVSS 8.7CVE-2026-53530GHSA-4HGP-59H5-GVRJ

ratex-parser panics on `\verb` with a multibyte delimiter (UTF-8 byte-boundary slice)

Answer in brief

CVE-2026-53530 records a High severity (CVSS 8.7) vulnerability in ratex-parser panics on `\verb` with a multibyte delimiter (UTF-8 byte-boundary slice). The current sources do not mark it as known exploited. The current feed maps erweixin/RaTeX (generic), ratex-parser (rust). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 21, 2026Updated Sep 9, 2026Source checked Sep 17, 2026First seen by HOL Jul 8, 2026Material review Sep 9, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.7
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 8.7. 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.

Affected scope and exposure questions

The current feed maps erweixin/RaTeX (generic), ratex-parser (rust). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
erweixin/RaTeXgeneric	< 0.1.11	Not reported
ratex-parserrust	<0.1.11	0.1.11

Recommended response

Check inventory. Check lockfiles and deployed manifests for erweixin/RaTeX, ratex-parser.
Review the reported fix. Update ratex-parser to 0.1.11 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 21, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Jul 8, 2026

Sources and claim methodology

Upstream source description

RaTeX is a KaTeX-compatible math rendering engine written in Rust. Prior to version 0.1.11, the public parser entrypoint `ratex_parser::parse(&str)` panics on the 9-byte input `\verbéxé` (i.e. `\verb` followed by the non-ASCII delimiter `é`). When handling a `\verb` command, the parser slices the verbatim argument with byte indices (`arg[1..arg.len() - 1]`); if the delimiter character is multibyte UTF-8, index `1` lands inside that character and Rust panics with *“byte index 1 is not a char boundary”*. Because RaTeX’s release profile sets `panic = "abort"` (`Cargo.toml:48`), the panic aborts the entire process — not just the current request/thread — making this a hard denial of service for any service that renders untrusted LaTeX. Version 0.1.11 fixes the issue.

Quoted source text, attributed separately from HOL analysis.