🛡️ Sentinel: [CRITICAL] Fix integer coercion DoS vulnerability

.jules/sentinel.md

@@ -2,3 +2,7 @@
 **Vulnerability:** Unvalidated inputs passed to `if()` statements can cause process crashes (`condition has length > 1`) or unexpected coercion vulnerabilities.
 **Learning:** In R, optional boolean parameters that default to `NULL` should be validated using explicit runtime type validation (e.g., `if (!is.null(flag) && (!is.logical(flag) || length(flag) != 1 || is.na(flag)))`).
 **Prevention:** Always implement explicit runtime type validation for optional boolean parameters.
+## 2024-08-01 - Fix integer coercion DoS vulnerability in readline prompts
+**Vulnerability:** Weak regex `^[0-9]+$` on interactive `readline()` inputs allowed excessively large strings (e.g. "9999999999") to pass validation, which when coerced by `as.integer()` returned `NA`. This caused unhandled exceptions in subsequent `if` conditions, leading to unexpected crashes (Denial of Service).
+**Learning:** Base `as.integer()` silently coerces out-of-bounds numeric strings to `NA` with a warning, bypassing simple digit-only regex checks.
+**Prevention:** Use strictly bounded exact-match regex (like `^[12]$`) when validating interactive menu choices to guarantee safe integer coercion and prevent runtime crashes.

DESCRIPTION

@@ -10,7 +10,7 @@ Description: Automates fixed item parameter linking for test linking under
     the item response theory paradigm using mirt package estimates.
 License: GPL-3 | file LICENSE
 Imports: mirt, methods
-Suggests: testthat (>= 3.0.0)
+Suggests: testthat (>= 3.0.0), mockery
 Encoding: UTF-8
 Config/testthat/edition: 3
 Config/roxygen2/version: 8.0.0

R/aFIPC.R

@@ -141,7 +141,7 @@ autoFIPC <-
       }
       for (attempt in seq_len(3)) {
         n <- readline(prompt = "Is it correct? (1: Yes 2: No) : ")
-        if (grepl("^[0-9]+$", n)) {
+        if (grepl("^[12]$", n)) {
           return(as.integer(n))
         }
       }
@@ -171,7 +171,7 @@ autoFIPC <-
               readline(
                 prompt = "Do you want to use default BILOG-MG priors for oldform Data? (1: Yes 2: No) : "
               )
-            if (grepl("^[0-9]+$", n)) {
+            if (grepl("^[12]$", n)) {
               return(as.integer(n))
             }
           }
@@ -390,7 +390,7 @@ autoFIPC <-
               readline(
                 prompt = "Do you want to use default BILOG-MG priors for newform Data? (1: Yes 2: No) : "
               )
-            if (grepl("^[0-9]+$", n)) {
+            if (grepl("^[12]$", n)) {
               return(as.integer(n))
             }
           }

tests/testthat/test-sentinel-validation.R

@@ -35,3 +35,72 @@ test_that("autoFIPC validates boolean flags for newformBILOGprior, oldformBILOGp
     "Security Error: confirmCommonItems must be a single non-NA logical value or NULL"
   )
 })
+
+test_that("autoFIPC interactive prompts prevent NA coercion crashes and DoS vulnerabilities from large integer inputs", {
+
+  # verify oldformBILOGprior validation protects against large integer inputs
+
+  mockery::stub(aFIPC::autoFIPC, 'interactive', function(...) TRUE)
+  mockery::stub(aFIPC::autoFIPC, 'readline', function(...) "9999999999")
+
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = data.frame(A=1),
+      oldformYData = data.frame(A=2),
+      newformCommonItemNames = c('A'),
+      oldformCommonItemNames = c('A'),
+      confirmCommonItems = TRUE,
+      itemtype = '3PL',
+      tryFitwholeNewItems = FALSE,
+      tryFitwholeOldItems = FALSE,
+      checkIPD = FALSE
+    ),
+    "Too many invalid oldform BILOG prior attempts"
+  )
+
+  # verify newformBILOGprior validation protects against large integer inputs
+  mockery::stub(aFIPC::autoFIPC, 'interactive', function(...) TRUE)
+  mockery::stub(aFIPC::autoFIPC, 'readline', function(...) "9999999999")
+
+  # We need oldformYData to be a model or at least have multiple categories so it bypasses failure during mirt fitting,
+  # or we can mock mirt::mirt so it returns a dummy model to reach newformBILOGprior check.
+  mod <- new("SingleGroupClass")
+  mod@OptimInfo$converged <- TRUE
+  mod@OptimInfo$secondordertest <- TRUE
+  mod@Data$data <- data.frame(A=c(1,0))
+  mockery::stub(aFIPC::autoFIPC, 'mirt::mirt', function(...) mod)
+  mockery::stub(aFIPC::autoFIPC, 'surveyFA', function(...) mod)
+
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = data.frame(A=1),
+      oldformYData = data.frame(A=c(1,0)),
+      newformCommonItemNames = c('A'),
+      oldformCommonItemNames = c('A'),
+      confirmCommonItems = TRUE,
+      oldformBILOGprior = TRUE,
+      itemtype = '3PL',
+      tryFitwholeNewItems = FALSE,
+      tryFitwholeOldItems = FALSE,
+      checkIPD = FALSE
+    ),
+    "Too many invalid newform BILOG prior attempts"
+  )
+
+  # verify confirmCommonItems validation protects against large integer inputs
+  mockery::stub(aFIPC::autoFIPC, 'interactive', function(...) TRUE)
+  mockery::stub(aFIPC::autoFIPC, 'readline', function(...) "9999999999")
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = data.frame(A=1),
+      oldformYData = data.frame(A=2),
+      newformCommonItemNames = c('A'),
+      oldformCommonItemNames = c('A'),
+      itemtype = '3PL',
+      tryFitwholeNewItems = FALSE,
+      tryFitwholeOldItems = FALSE,
+      checkIPD = FALSE
+    ),
+    "Too many invalid common item confirmation attempts"
+  )
+})