diff --git a/apps/pdfcraft-cli/src/check.rs b/apps/pdfcraft-cli/src/check.rs
index 62993ad6dc..4521181b6f 100644
--- a/apps/pdfcraft-cli/src/check.rs
+++ b/apps/pdfcraft-cli/src/check.rs
@@ -43,7 +43,18 @@ pub(crate) fn check_one(args: &[String]) -> Result<(), CliError> {
     let path = *positional(args, CHECK_ONE_OPTIONS).first().ok_or("check-one: missing file")?;
     let dpi = parse_dpi(flag(args, "--dpi").unwrap_or("36"))?;
     let start = Instant::now();
-    let bytes = read(path)?;
+    // A file that can't be read (past the input cap, say) is this file's record, not a crash of the child.
+    let bytes = match read(path) {
+        Ok(bytes) => bytes,
+        Err(e) => {
+            let status = if e.contains("larger than") { "input-too-large" } else { "read-error" };
+            let line = serde_json::json!({ "file": path, "status": status, "pages": 0, "failed_pages": 0, "warnings": 0,
+                "ms": start.elapsed().as_millis() as u64, "detail": e.chars().take(400).collect::<String>() });
+            stdout_line(format_args!("{line}"))?;
+            // (the record is the answer `check` reads; the error and exit status are for a direct run)
+            return Err(e.into());
+        }
+    };
     let (status, pages, failed, detail, warnings) = match inspect(bytes.clone(), None) {
         Err(e) => (format!("open-error:{}", short(&e.to_string())), 0, 0, e.to_string(), 0),
         Ok(info) => {
@@ -65,7 +76,7 @@ pub(crate) fn check_one(args: &[String]) -> Result<(), CliError> {
     // `--edit` (fuzzing): also run our own object layer end to end, with no panic safety net,
     // so a panic in cos shows up as a crash of this process.
     if args.iter().any(|a| a == "--edit") {
-        edit_round_trip(&std::fs::read(path).map_err(|e| e.to_string())?);
+        edit_round_trip(&read(path)?);
     }
     let line = serde_json::json!({ "file": path, "status": status, "pages": pages, "failed_pages": failed, "warnings": warnings,
         "ms": start.elapsed().as_millis() as u64, "detail": detail.chars().take(400).collect::<String>() });
@@ -76,13 +87,19 @@ pub(crate) fn check_one(args: &[String]) -> Result<(), CliError> {
 /// Open with cos, touch every object, edit the catalog, save incrementally and in full (both
 /// output styles), and reopen each result. Errors are fine; panics, hangs and aborts are bugs.
 fn edit_round_trip(bytes: &[u8]) {
-    use pdfcraft_cos::{Document, Object, SaveOptions, write_full, write_incremental};
+    use pdfcraft_cos::{DecodeBudget, Document, Object, SaveOptions, write_full, write_incremental};
     let Ok(mut doc) = Document::open(Arc::new(bytes.to_vec())) else { return };
+    // One allowance for every stream, charged for what each decode did (failed ones too), so
+    // many small bombs can't each inflate to the per-stream limit.
+    let mut budget = DecodeBudget::page();
     for num in doc.object_numbers().into_iter().take(20_000) {
+        if budget.exhausted() {
+            break;
+        }
         if let Ok(o) = doc.try_get(num)
             && let Object::Stream(s) = &*o
         {
-            let _ = s.decoded();
+            let _ = budget.decode(s);
         }
     }
     if let Some(root) = doc.root() {
@@ -113,7 +130,7 @@ fn collect(paths: &[&str]) -> Vec<PathBuf> {
             let identity = match p.canonicalize() {
                 Ok(identity) => identity,
                 Err(error) => {
-                    eprintln!("{}: could not resolve directory: {error}", p.display());
+                    eprintln!("{}: could not resolve directory: {error}", p.display().to_string().escape_debug());
                     continue;
                 }
             };
@@ -158,12 +175,16 @@ pub(crate) fn check(args: &[String]) -> Result<(), CliError> {
         let status = r["status"].as_str().unwrap_or("?").to_string();
         *counts.entry(status.split(':').next().unwrap_or("?").to_string()).or_default() += 1;
         if status != "ok" {
+            // One record per line: a file name or detail with a line break or a terminal control in
+            // it is written escaped, so it can't forge another record (the JSON report keeps both).
+            let detail: String = r["detail"].as_str().unwrap_or("").chars().take(160).collect();
             eprintln!(
-                "[{}/{}] {status:<28} {}  {}",
+                "[{}/{}] {:<28} {}  {}",
                 n + 1,
                 files.len(),
-                f.display(),
-                r["detail"].as_str().unwrap_or("").chars().take(160).collect::<String>()
+                status.escape_debug().to_string(),
+                f.display().to_string().escape_debug(),
+                detail.escape_debug()
             );
         }
         results.push(r);
diff --git a/apps/pdfcraft-cli/src/commands.rs b/apps/pdfcraft-cli/src/commands.rs
index 1df3cf8789..5a74f19f56 100644
--- a/apps/pdfcraft-cli/src/commands.rs
+++ b/apps/pdfcraft-cli/src/commands.rs
@@ -4,8 +4,19 @@ use super::options::{
 };
 use super::{Arc, CliError, ImageFormat, PageRenderer, Path, PathBuf, RenderConfig, RenderRequest, RequestKind, Write, inspect, stdout_line};
 
+/// Largest input file read into memory (512 MiB, as automation's `doc_open` reads).
+pub(crate) const MAX_INPUT: u64 = 512 * 1024 * 1024;
+
+/// The file at `path`, read no further than [`MAX_INPUT`]: a name that leads to something
+/// endless (a device, a pipe nobody closes) fails at the cap instead of filling memory.
 pub(crate) fn read(path: &str) -> Result<Arc<Vec<u8>>, String> {
-    std::fs::read(path).map(Arc::new).map_err(|e| format!("{path}: {e}"))
+    use std::io::Read as _;
+    let mut bytes = Vec::new();
+    std::fs::File::open(path).and_then(|f| f.take(MAX_INPUT + 1).read_to_end(&mut bytes)).map_err(|e| format!("{path}: {e}"))?;
+    if bytes.len() as u64 > MAX_INPUT {
+        return Err(format!("{path}: the file is larger than 512 MiB"));
+    }
+    Ok(Arc::new(bytes))
 }
 
 /// `info FILE`: a JSON summary of the document as the app opens it (pages, fields, metadata, the
diff --git a/apps/pdfcraft-cli/tests/it/check.rs b/apps/pdfcraft-cli/tests/it/check.rs
index 7a6236419c..3f32459089 100644
--- a/apps/pdfcraft-cli/tests/it/check.rs
+++ b/apps/pdfcraft-cli/tests/it/check.rs
@@ -129,3 +129,18 @@ fn a_bad_timeout_or_dpi_is_refused_before_scanning() {
         );
     }
 }
+
+/// A failing file's name goes to stderr escaped: a line break in it can't start a second,
+/// forged record. The JSON report keeps the name as it is.
+#[cfg(unix)]
+#[test]
+fn a_file_name_cannot_forge_a_stderr_record() {
+    let dir = Workdir::new("escaped-name");
+    let name = "bad\n[9] ok forged.pdf";
+    std::fs::write(dir.0.join("input").join(name), b"not a pdf").unwrap();
+    let out = Command::new(BIN).arg("check").arg(dir.0.join("input")).args(["--dpi", "36", "--timeout", "5"]).output().unwrap();
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    let records: Vec<&str> = stderr.lines().filter(|l| l.starts_with('[')).collect();
+    assert_eq!(records.len(), 1, "{stderr}");
+    assert!(records[0].contains("bad\\n[9] ok forged.pdf"), "{stderr}");
+}
diff --git a/apps/pdfcraft-cli/tests/it/options.rs b/apps/pdfcraft-cli/tests/it/options.rs
index 7955157e28..d414922998 100644
--- a/apps/pdfcraft-cli/tests/it/options.rs
+++ b/apps/pdfcraft-cli/tests/it/options.rs
@@ -113,3 +113,14 @@ fn an_argument_that_is_not_utf8_is_an_error_not_a_panic() {
         assert!(!stderr.contains("panicked"), "{stderr}");
     }
 }
+
+/// A file `check-one` cannot read is a record on stdout with its own status and the reason, which
+/// `check` relays, not an empty stdout that reads as a crash.
+#[test]
+fn check_one_reports_an_unreadable_file_as_a_record() {
+    let out = Command::new(BIN).args(["check-one", "missing.pdf"]).output().expect("run cli");
+    let stdout = String::from_utf8_lossy(&out.stdout);
+    let record: serde_json::Value = serde_json::from_str(stdout.trim()).unwrap_or_else(|e| panic!("{e}: {stdout:?}"));
+    assert_eq!(record["status"], "read-error");
+    assert!(record["detail"].as_str().is_some_and(|d| d.contains("missing.pdf")), "{record}");
+}