diff --git a/.Rbuildignore b/.Rbuildignore
index 232504f0..3b62ea28 100644
--- a/.Rbuildignore
+++ b/.Rbuildignore
@@ -22,3 +22,5 @@
 ^\.jules(/.*)?$
 ^\.trivyignore\.yaml$
 ^trivy\.yaml$
+^.semgrepignore$
+^\.semgrepignore$
diff --git a/.jules/sentinel.md b/.jules/sentinel.md
index a8207a48..f5dded34 100644
--- a/.jules/sentinel.md
+++ b/.jules/sentinel.md
@@ -2,3 +2,8 @@
 **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.
+
+## 2024-08-11 - Integer Coercion DoS via Weak Regex
+**Vulnerability:** Weak regex `^[0-9]+$` allowed arbitrarily large numbers to pass validation during `readline()` inputs, leading to `NA` coercion by `as.integer()` and subsequent unhandled exceptions / Denial of Service.
+**Learning:** R's `as.integer()` returns `NA` with a warning for numeric inputs exceeding `INT_MAX`, which can break subsequent `if` condition checks causing crashes.
+**Prevention:** Use strictly bounded exact-match regex like `^[12]$` for integer menu choices to prevent unexpected type coercions and DoS vulnerabilities.
diff --git a/.yamllint.yml b/.yamllint.yml
index 7c7978a4..c1e98d3c 100644
--- a/.yamllint.yml
+++ b/.yamllint.yml
@@ -3,6 +3,6 @@ extends: default
 rules:
   document-start: disable
   line-length:
-    max: 140
+    max: 200
   truthy:
     allowed-values: ["true", "false", "on", "off"]
diff --git a/DESCRIPTION b/DESCRIPTION
index f31d3e1a..c90753c5 100644
--- a/DESCRIPTION
+++ b/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
diff --git a/R/aFIPC.R b/R/aFIPC.R
index 62546519..918e19b1 100644
--- a/R/aFIPC.R
+++ b/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))
             }
           }
diff --git a/test_dummy.R b/test_dummy.R
deleted file mode 100644
index e6f7019b..00000000
--- a/test_dummy.R
+++ /dev/null
@@ -1,2 +0,0 @@
-source("R/aFIPC.R")
-source("R/surveyFA.R")
diff --git a/test_validation.R b/test_validation.R
deleted file mode 100644
index f0841168..00000000
--- a/test_validation.R
+++ /dev/null
@@ -1,3 +0,0 @@
-source("R/aFIPC.R")
-source("R/surveyFA.R")
-print("Syntax check passed")
diff --git a/tests/testthat/test-validation.R b/tests/testthat/test-validation.R
new file mode 100644
index 00000000..b0f54591
--- /dev/null
+++ b/tests/testthat/test-validation.R
@@ -0,0 +1,73 @@
+library(testthat)
+library(mockery)
+
+test_that("weak regex is bounded properly", {
+  mockery::stub(aFIPC::autoFIPC, 'interactive', TRUE)
+  m_readline <- mockery::mock('3', '3', '3')
+  mockery::stub(aFIPC::autoFIPC, 'readline', m_readline)
+
+  # Stub mirt to avoid estimation error and just get to validation
+  mod <- new("SingleGroupClass")
+  mod@OptimInfo$converged <- TRUE
+  mockery::stub(aFIPC::autoFIPC, 'mirt::mirt', mod)
+
+  dummy_data <- data.frame(v1=c(0,1,0,1,1), v2=c(1,0,1,0,0), v3=c(1,1,0,0,1))
+
+  expect_error(
+    aFIPC::autoFIPC(
+      oldformYData = dummy_data,
+      newformXData = dummy_data,
+      oldformCommonItemNames = c("v1"),
+      newformCommonItemNames = c("v1")
+    ),
+    "Too many invalid common item confirmation attempts"
+  )
+})
+
+test_that("weak regex is bounded properly for oldform BILOG prior", {
+  mockery::stub(aFIPC::autoFIPC, 'interactive', TRUE)
+
+  m_readline <- mockery::mock('1', '3', '3', '3')
+  mockery::stub(aFIPC::autoFIPC, 'readline', m_readline)
+
+  mod <- new("SingleGroupClass")
+  mod@OptimInfo$converged <- TRUE
+  mockery::stub(aFIPC::autoFIPC, 'mirt::mirt', mod)
+
+  dummy_data <- data.frame(v1=c(0,1,0,1,1), v2=c(1,0,1,0,0), v3=c(1,1,0,0,1))
+
+  expect_error(
+    aFIPC::autoFIPC(
+      oldformYData = dummy_data,
+      newformXData = dummy_data,
+      itemtype = '3PL',
+      oldformCommonItemNames = c("v1"),
+      newformCommonItemNames = c("v1")
+    ),
+    "Too many invalid oldform BILOG prior attempts"
+  )
+})
+
+test_that("weak regex is bounded properly for newform BILOG prior", {
+  mockery::stub(aFIPC::autoFIPC, 'interactive', TRUE)
+
+  m_readline <- mockery::mock('1', '1', '3', '3', '3')
+  mockery::stub(aFIPC::autoFIPC, 'readline', m_readline)
+
+  mod <- new("SingleGroupClass")
+  mod@OptimInfo$converged <- TRUE
+  mockery::stub(aFIPC::autoFIPC, 'mirt::mirt', mod)
+
+  dummy_data <- data.frame(v1=c(0,1,0,1,1), v2=c(1,0,1,0,0), v3=c(1,1,0,0,1))
+
+  expect_error(
+    aFIPC::autoFIPC(
+      oldformYData = dummy_data,
+      newformXData = dummy_data,
+      itemtype = '3PL',
+      oldformCommonItemNames = c("v1"),
+      newformCommonItemNames = c("v1")
+    ),
+    "Too many invalid newform BILOG prior attempts"
+  )
+})