diff --git a/modules/imgproc/src/bilateral_filter.dispatch.cpp b/modules/imgproc/src/bilateral_filter.dispatch.cpp
index 8e0f1f5a95..1cc21521f6 100644
--- a/modules/imgproc/src/bilateral_filter.dispatch.cpp
+++ b/modules/imgproc/src/bilateral_filter.dispatch.cpp
@@ -321,7 +321,7 @@ bilateralFilter_32f( const Mat& src, Mat& dst, int d,
         }
 
     // parallel_for usage
-    CV_CPU_DISPATCH(bilateralFilterInvoker_32f, (cn, radius, maxk, space_ofs, temp, dst, scale_index, space_weight, expLUT),
+    CV_CPU_DISPATCH(bilateralFilterInvoker_32f, (cn, radius, maxk, space_ofs, temp, dst, scale_index, space_weight, expLUT, kExpNumBins),
         CV_CPU_DISPATCH_MODES_ALL);
 }
 
diff --git a/modules/imgproc/src/bilateral_filter.simd.hpp b/modules/imgproc/src/bilateral_filter.simd.hpp
index ab718eac91..d03ef01f59 100644
--- a/modules/imgproc/src/bilateral_filter.simd.hpp
+++ b/modules/imgproc/src/bilateral_filter.simd.hpp
@@ -58,7 +58,7 @@ void bilateralFilterInvoker_8u(
         int* space_ofs, float *space_weight, float *color_weight);
 void bilateralFilterInvoker_32f(
         int cn, int radius, int maxk, int *space_ofs,
-        const Mat& temp, Mat& dst, float scale_index, float *space_weight, float *expLUT);
+        const Mat& temp, Mat& dst, float scale_index, float *space_weight, float *expLUT, int kExpNumBins);
 
 #ifndef CV_CPU_OPTIMIZATION_DECLARATIONS_ONLY
 
@@ -495,9 +495,9 @@ class BilateralFilter_32f_Invoker :
 public:
 
     BilateralFilter_32f_Invoker(int _cn, int _radius, int _maxk, int *_space_ofs,
-        const Mat& _temp, Mat& _dest, float _scale_index, float *_space_weight, float *_expLUT) :
+        const Mat& _temp, Mat& _dest, float _scale_index, float *_space_weight, float *_expLUT, int _kExpNumBins) :
         cn(_cn), radius(_radius), maxk(_maxk), space_ofs(_space_ofs),
-        temp(&_temp), dest(&_dest), scale_index(_scale_index), space_weight(_space_weight), expLUT(_expLUT)
+        temp(&_temp), dest(&_dest), scale_index(_scale_index), space_weight(_space_weight), expLUT(_expLUT), kExpNumBins(_kExpNumBins)
     {
     }
 
@@ -550,7 +550,7 @@ public:
                         v_float32 val0 = vx_load(ksptr);
                         v_float32 knan0 = v_not_nan(val0);
                         v_float32 alpha0 = v_and(v_and(v_mul(v_absdiff(val0, rval0), sindex), v_not_nan(rval0)), knan0);
-                        v_int32 idx0 = v_trunc(alpha0);
+                        v_int32 idx0 = v_min(v_trunc(alpha0), vx_setall_s32(kExpNumBins));
                         alpha0 = v_sub(alpha0, v_cvt_f32(idx0));
                         v_float32 w0 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx0), alpha0, v_mul(v_lut(this->expLUT, idx0), v_sub(v_one, alpha0)))), knan0);
                         v_wsum0 = v_add(v_wsum0, w0);
@@ -560,7 +560,7 @@ public:
                         v_float32 val1 = vx_load(ksptr + nlanes);
                         v_float32 knan1 = v_not_nan(val1);
                         v_float32 alpha1 = v_and(v_and(v_mul(v_absdiff(val1, rval1), sindex), v_not_nan(rval1)), knan1);
-                        v_int32 idx1 = v_trunc(alpha1);
+                        v_int32 idx1 = v_min(v_trunc(alpha1), vx_setall_s32(kExpNumBins));
                         alpha1 = v_sub(alpha1, v_cvt_f32(idx1));
                         v_float32 w1 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx1), alpha1, v_mul(v_lut(this->expLUT, idx1), v_sub(v_one, alpha1)))), knan1);
                         v_wsum1 = v_add(v_wsum1, w1);
@@ -570,7 +570,7 @@ public:
                         v_float32 val2 = vx_load(ksptr + nlanes_2);
                         v_float32 knan2 = v_not_nan(val2);
                         v_float32 alpha2 = v_and(v_and(v_mul(v_absdiff(val2, rval2), sindex), v_not_nan(rval2)), knan2);
-                        v_int32 idx2 = v_trunc(alpha2);
+                        v_int32 idx2 = v_min(v_trunc(alpha2), vx_setall_s32(kExpNumBins));
                         alpha2 = v_sub(alpha2, v_cvt_f32(idx2));
                         v_float32 w2 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx2), alpha2, v_mul(v_lut(this->expLUT, idx2), v_sub(v_one, alpha2)))), knan2);
                         v_wsum2 = v_add(v_wsum2, w2);
@@ -580,7 +580,7 @@ public:
                         v_float32 val3 = vx_load(ksptr + nlanes_3);
                         v_float32 knan3 = v_not_nan(val3);
                         v_float32 alpha3 = v_and(v_and(v_mul(v_absdiff(val3, rval3), sindex), v_not_nan(rval3)), knan3);
-                        v_int32 idx3 = v_trunc(alpha3);
+                        v_int32 idx3 = v_min(v_trunc(alpha3), vx_setall_s32(kExpNumBins));
                         alpha3 = v_sub(alpha3, v_cvt_f32(idx3));
                         v_float32 w3 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx3), alpha3, v_mul(v_lut(this->expLUT, idx3), v_sub(v_one, alpha3)))), knan3);
                         v_wsum3 = v_add(v_wsum3, w3);
@@ -611,7 +611,7 @@ public:
                         v_float32 val0 = vx_load(ksptr);
                         v_float32 knan0 = v_not_nan(val0);
                         v_float32 alpha0 = v_and(v_and(v_mul(v_absdiff(val0, rval0), sindex), rval0_not_nan), knan0);
-                        v_int32 idx0 = v_trunc(alpha0);
+                        v_int32 idx0 = v_min(v_trunc(alpha0), vx_setall_s32(kExpNumBins));
                         alpha0 = v_sub(alpha0, v_cvt_f32(idx0));
                         v_float32 w0 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx0), alpha0, v_mul(v_lut(this->expLUT, idx0), v_sub(v_one, alpha0)))), knan0);
                         v_wsum0 = v_add(v_wsum0, w0);
@@ -621,7 +621,7 @@ public:
                         v_float32 val1 = vx_load(ksptr + nlanes);
                         v_float32 knan1 = v_not_nan(val1);
                         v_float32 alpha1 = v_and(v_and(v_mul(v_absdiff(val1, rval1), sindex), rval1_not_nan), knan1);
-                        v_int32 idx1 = v_trunc(alpha1);
+                        v_int32 idx1 = v_min(v_trunc(alpha1), vx_setall_s32(kExpNumBins));
                         alpha1 = v_sub(alpha1, v_cvt_f32(idx1));
                         v_float32 w1 = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx1), alpha1, v_mul(v_lut(this->expLUT, idx1), v_sub(v_one, alpha1)))), knan1);
                         v_wsum1 = v_add(v_wsum1, w1);
@@ -640,7 +640,7 @@ public:
                     {
                         const float* ksptr = sptr_j + space_ofs[k];
                         float val = *ksptr;
-                        float alpha = std::abs(val - rval) * scale_index;
+                        float alpha = std::min(std::abs(val - rval) * scale_index, (float)kExpNumBins);
                         int idx = cvFloor(alpha);
                         alpha -= idx;
                         if (!cvIsNaN(val))
@@ -681,7 +681,7 @@ public:
 
                         v_float32 knan = v_and(v_and(v_not_nan(kb), v_not_nan(kg)), v_not_nan(kr));
                         v_float32 alpha = v_and(v_and(v_and(v_and(v_mul(v_add(v_add(v_absdiff(kb, rb), v_absdiff(kg, rg)), v_absdiff(kr, rr)), sindex), v_not_nan(rb)), v_not_nan(rg)), v_not_nan(rr)), knan);
-                        v_int32 idx = v_trunc(alpha);
+                        v_int32 idx = v_min(v_trunc(alpha), vx_setall_s32(kExpNumBins));
                         alpha = v_sub(alpha, v_cvt_f32(idx));
 
                         v_float32 w = v_and(v_mul(kweight, v_muladd(v_lut(this->expLUT + 1, idx), alpha, v_mul(v_lut(this->expLUT, idx), v_sub(v_one, alpha)))), knan);
@@ -709,7 +709,7 @@ public:
                         bool v_NAN = cvIsNaN(b) || cvIsNaN(g) || cvIsNaN(r);
                         float rb = rsptr[0], rg = rsptr[1], rr = rsptr[2];
                         bool r_NAN = cvIsNaN(rb) || cvIsNaN(rg) || cvIsNaN(rr);
-                        float alpha = (std::abs(b - rb) + std::abs(g - rg) + std::abs(r - rr)) * scale_index;
+                        float alpha = std::min((std::abs(b - rb) + std::abs(g - rg) + std::abs(r - rr)) * scale_index, (float)kExpNumBins);
                         int idx = cvFloor(alpha);
                         alpha -= idx;
                         if (!v_NAN)
@@ -753,17 +753,18 @@ private:
     const Mat* temp;
     Mat *dest;
     float scale_index, *space_weight, *expLUT;
+    int kExpNumBins;
 };
 
 } // namespace anon
 
 void bilateralFilterInvoker_32f(
         int cn, int radius, int maxk, int *space_ofs,
-        const Mat& temp, Mat& dst, float scale_index, float *space_weight, float *expLUT)
+        const Mat& temp, Mat& dst, float scale_index, float *space_weight, float *expLUT, int kExpNumBins)
 {
     CV_INSTRUMENT_REGION();
 
-    BilateralFilter_32f_Invoker body(cn, radius, maxk, space_ofs, temp, dst, scale_index, space_weight, expLUT);
+    BilateralFilter_32f_Invoker body(cn, radius, maxk, space_ofs, temp, dst, scale_index, space_weight, expLUT, kExpNumBins);
     parallel_for_(Range(0, dst.rows), body, dst.total()/(double)(1<<16));
 }
 
diff --git a/modules/imgproc/test/test_bilateral_filter.cpp b/modules/imgproc/test/test_bilateral_filter.cpp
index 8f800a1215..36d43c6795 100644
--- a/modules/imgproc/test/test_bilateral_filter.cpp
+++ b/modules/imgproc/test/test_bilateral_filter.cpp
@@ -291,4 +291,33 @@ namespace opencv_test { namespace {
         test.safe_run();
     }
 
+    // Regression test for issue #28254
+    // Out-of-bounds read in AVX2 bilateralFilter 32f path with BORDER_CONSTANT
+    TEST(Imgproc_BilateralFilter, regression_28254_oob_read)
+    {
+        // Create a 64x64 CV_32FC1 image with values in range [100, 200]
+        // Image must be large enough (width >= 32) to trigger SIMD/AVX2 code path.
+        // Values are set so BORDER_CONSTANT padding (default 0) is outside the range,
+        // which triggers the out-of-bounds condition in the LUT access.
+        cv::Mat src(64, 64, CV_32FC1);
+        cv::randu(src, 100.0f, 200.0f);
+        cv::Mat dst;
+
+        // Parameters that trigger the bug
+        int d = -1;
+        double sigmaColor = 2.7;
+        double sigmaSpace = 44.5;
+        int borderType = cv::BORDER_CONSTANT;
+
+        // This should not crash or trigger AddressSanitizer
+        EXPECT_NO_THROW(
+            cv::bilateralFilter(src, dst, d, sigmaColor, sigmaSpace, borderType)
+        );
+
+        // Verify output is valid
+        EXPECT_FALSE(dst.empty());
+        EXPECT_EQ(dst.size(), src.size());
+        EXPECT_EQ(dst.type(), src.type());
+    }
+
 }} // namespace