GHSA-px68-xx5g-48q5 dcmjs: DS/IS VALUE REPRESENTATION INPUT VALIDATION BYPASS

• npm dcmjs: < 0.52.0 → fixed in 0.52.0

dcmjs, a JavaScript library for DICOM manipulation used in web-based medical imaging viewers, contains an input validation bypass in its handling of DS (Decimal String) and IS (Integer String) value representations. The DecimalString and IntegerString classes in ValueRepresentation.js use a regex sanitizer followed by JavaScript's Number() constructor. While the regex strips direct NaN/Infinity strings, it preserves scientific notation (including the 'e' character), enabling: 1. Infinity injection via scientific notation overflow (1e999999) 2. NaN injection via sign-only remnants from stripped inf strings ("-inf" -> "-") 3. IS accepting scientific notation in violation of PS3.5 AFFECTED PRODUCT ================ Product: dcmjs (JavaScript DICOM manipulation library) Repository: https://github.com/dcmjs-org/dcmjs npm: https://www.npmjs.com/package/dcmjs Affected Versions: 100000) in violation of PS3.5 Section 6.2, which restricts IS to characters 0-9, +, -. (d) No range validation exists for IS values (PS3.5 requires [-2^31, 2^31-1]) or DS values (16-character max, fixed/floating-point only). VULNERABILITY DETAILS ===================== Attack Vector 1: Infinity via Scientific Notation Overflow ---------------------------------------------------------- Input: DS or IS field containing "1e999999" Regex: Passes (all chars in allowed set) Result: Number("1e999999") -> Infinity Impact: Infinity propagates through all downstream arithmetic Attack Vector 2: Negative Infinity via Scientific Notation ---------------------------------------------------------- Input: DS or IS field containing "-1e999999" Regex: Passes Result: Number("-1e999999") -> -Infinity Impact: Negative Infinity in spatial/dosimetric calculations Attack Vector 3: NaN via Sign-Only Remnant ------------------------------------------ Input: DS or IS field containing "-inf" Regex: Strips to "-" Result: Number("-") -> NaN Impact: NaN propagates silently through arithmetic (IEEE 754) Attack Vector 4: NaN via Plus-Only Remnant ------------------------------------------ Input: DS or IS field containing "+inf" Regex: Strips to "+" Result: Number("+") -> NaN Impact: Same as above Attack Vector 5: IS Scientific Notation Bypass ----------------------------------------------- Input: IS field containing "1e5" Regex: Passes Result: Number("1e5") -> 100000 Impact: Integer fields accept non-integer representation, violating PS3.5 Attack Vector 6: IS Extreme Overflow ------------------------------------- Input: IS field containing "1e18" Regex: Passes Result: Number("1e18") -> 1000000000000000000 Impact: Far exceeds IS range [-2^31, 2^31-1], no bounds check CLINICAL IMPACT =============== dcmjs is used in web-based DICOM viewers and processing pipelines. Corrupted values affect: • PixelSpacing / ImagePositionPatient: Spatial geometry corruption prevents accurate measurement and registration in web viewers • WindowCenter / WindowWidth: Display pipeline corruption makes images unreadable (all black or all white) • DoseGridScaling / NumberOfFrames: Radiation therapy dose display errors and denial of service via frame count overflow • RescaleSlope / RescaleIntercept: Hounsfield unit conversion produces invalid values, corrupting quantitative analysis • SliceThickness: Volume reconstruction fails in multiplanar reformats