diff --git a/src/extensions/parser.rs b/src/extensions/parser.rs
index d7b6384..05f3482 100644
--- a/src/extensions/parser.rs
+++ b/src/extensions/parser.rs
@@ -22,6 +22,7 @@ use crate::{
             sum::Sum,
         },
         error::LogriaError,
+        sanitizers::sanitize_filename,
     },
 };
 
@@ -54,9 +55,10 @@ impl ExtensionMethods for Parser {
     /// Create parser file from a Parser struct
     fn save(self, file_name: &str) -> Result<(), LogriaError> {
         let parser_json = serde_json::to_string_pretty(&self).unwrap();
-        let path = format!("{}/{}", patterns(), file_name);
+        let sanitized_filename = sanitize_filename(file_name);
+        let path = format!("{}/{}", patterns(), sanitized_filename);
 
-        match write(format!("{}/{}", patterns(), file_name), parser_json) {
+        match write(&path, parser_json) {
             Ok(()) => Ok(()),
             Err(why) => Err(LogriaError::CannotWrite(path, <dyn Error>::to_string(&why))),
         }
diff --git a/src/extensions/session.rs b/src/extensions/session.rs
index 3bbd97a..bbc4037 100644
--- a/src/extensions/session.rs
+++ b/src/extensions/session.rs
@@ -11,7 +11,7 @@ use serde::{Deserialize, Serialize};
 use crate::{
     constants::{cli::excludes::SESSION_FILE_EXCLUDES, directories::sessions},
     extensions::extension::ExtensionMethods,
-    util::error::LogriaError,
+    util::{error::LogriaError, sanitizers::sanitize_filename},
 };
 
 #[derive(Eq, Hash, PartialEq, Serialize, Deserialize, Debug)]
@@ -39,7 +39,8 @@ impl ExtensionMethods for Session {
     /// Create session file from a Session struct
     fn save(self, file_name: &str) -> Result<(), LogriaError> {
         let session_json = serde_json::to_string_pretty(&self).unwrap();
-        let path = format!("{}/{}", sessions(), file_name);
+        let sanitized_filename = sanitize_filename(file_name);
+        let path = format!("{}/{}", sessions(), sanitized_filename);
         match write(&path, session_json) {
             Ok(()) => Ok(()),
             Err(why) => Err(LogriaError::CannotWrite(path, <dyn Error>::to_string(&why))),
diff --git a/src/util/sanitizers.rs b/src/util/sanitizers.rs
index 5101399..5bac030 100644
--- a/src/util/sanitizers.rs
+++ b/src/util/sanitizers.rs
@@ -1,8 +1,34 @@
+use std::{cmp::max, collections::HashSet, str::from_utf8, sync::LazyLock};
+
 use regex::bytes::Regex;
-use std::{cmp::max, str::from_utf8};
 
 use crate::constants::cli::patterns::ANSI_COLOR_PATTERN;
 
+/// Characters disallowed in a filename
+static FILENAME_DISALLOWED_CHARS: LazyLock<HashSet<char>> =
+    LazyLock::new(|| HashSet::from(['*', '"', '/', '\\', '<', '>', ':', '|', '?', '.']));
+/// The character to replace disallowed chars with
+const FILENAME_REPLACEMENT_CHAR: char = '_';
+
+/// Remove unsafe chars in [this list](FILENAME_DISALLOWED_CHARS).
+///
+/// Does not need to use a `Cow` for optimization because the source is always generated based on chat data
+/// so there is no opportunity for the original input to be passed in from another borrow.
+pub fn sanitize_filename(filename: &str) -> String {
+    filename
+        .trim()
+        .chars()
+        .map(|letter| {
+            if letter.is_control() || FILENAME_DISALLOWED_CHARS.contains(&letter) {
+                FILENAME_REPLACEMENT_CHAR
+            } else {
+                letter
+            }
+        })
+        .take(255)
+        .collect()
+}
+
 pub struct LengthFinder {
     color_pattern: Regex,
 }
@@ -34,7 +60,7 @@ impl LengthFinder {
 
 #[cfg(test)]
 mod tests {
-    use crate::util::sanitizers::LengthFinder;
+    use crate::util::sanitizers::{LengthFinder, sanitize_filename};
 
     #[test]
     fn test_length_clean() {
@@ -81,4 +107,44 @@ mod tests {
         assert_eq!(rows, 1);
         assert_eq!(length, 6);
     }
+
+    #[test]
+    fn test_sanitize_filename_clean() {
+        assert_eq!(sanitize_filename("normal_filename"), "normal_filename");
+        assert_eq!(sanitize_filename("file.txt"), "file_txt");
+        assert_eq!(sanitize_filename("file_123"), "file_123");
+    }
+
+    #[test]
+    fn test_sanitize_filename_invalid_chars() {
+        assert_eq!(sanitize_filename("file<>name"), "file__name");
+        assert_eq!(sanitize_filename("file:name"), "file_name");
+        assert_eq!(sanitize_filename("file\"name"), "file_name");
+        assert_eq!(sanitize_filename("file|name"), "file_name");
+        assert_eq!(sanitize_filename("file?name"), "file_name");
+        assert_eq!(sanitize_filename("file*name"), "file_name");
+        assert_eq!(sanitize_filename("file\\name"), "file_name");
+        assert_eq!(sanitize_filename("file/name"), "file_name");
+    }
+
+    #[test]
+    fn test_sanitize_filename_control_chars() {
+        assert_eq!(sanitize_filename("file\x00name"), "file_name");
+        assert_eq!(sanitize_filename("file\x1fname"), "file_name");
+        assert_eq!(sanitize_filename("file\x7fname"), "file_name");
+    }
+
+    #[test]
+    fn test_sanitize_filename_trim() {
+        assert_eq!(sanitize_filename("  filename  "), "filename");
+        assert_eq!(sanitize_filename("..filename.."), "__filename__");
+        assert_eq!(sanitize_filename("\tfilename\t"), "filename");
+    }
+
+    #[test]
+    fn test_sanitize_filename_long() {
+        let long_name = "a".repeat(300);
+        let sanitized = sanitize_filename(&long_name);
+        assert_eq!(sanitized.len(), 255);
+    }
 }