Update Security section in manual.

Alert readers to a threat relating to iframe in HTML.
Add LaTeX, Typst to the list of formats that have an `include`.

Closes #10682.

1 files changed, 17 insertions, 8 deletions

diff --git a/MANUAL.txt b/MANUAL.txt
index d57682318..59178d8d8 100644
--- a/MANUAL.txt
+++ b/MANUAL.txt
@@ -7638,11 +7638,11 @@ For full documentation, see the [pandoc-lua] man page.
    writer could in principle do anything on your file system. Please
    audit filters and custom writers very carefully before using them.
 
-2. Several input formats (including HTML, Org, and RST) support `include`
-   directives that allow the contents of a file to be included in the
-   output. An untrusted attacker could use these to view the contents of
-   files on the file system.  (Using the `--sandbox` option can
-   protect against this threat.)
+2. Several input formats (including LaTeX, Org, RST, and Typst)
+   support `include` directives that allow the contents of a file to be
+   included in the output. An untrusted attacker could use these
+   to view the contents of files on the file system. (Using the
+   `--sandbox` option can protect against this threat.)
 
 3. Several output formats (including RTF, FB2, HTML with
    `--self-contained`, EPUB, Docx, and ODT) will embed encoded
@@ -7652,7 +7652,16 @@ For full documentation, see the [pandoc-lua] man page.
    against this threat, but will also prevent including images in
    these formats.)
 
-4. If your application uses pandoc as a Haskell library (rather than
+4. In reading HTML files, pandoc will attempt to include the
+   contents of `iframe` elements by fetching content from the
+   local file or URL specified by `src`. If untrusted HTML is
+   processed on a server, this has the potential to reveal anything
+   readable by the process running the server. Using the `-f html+raw_html`
+   will mitigate this threat by causing the whole `iframe`
+   to be parsed as a raw HTML block. Using `--sandbox will also
+   protect against the threat.
+
+5. If your application uses pandoc as a Haskell library (rather than
    shelling out to the executable), it is possible to use it in a mode
    that fully isolates pandoc from your file system, by running the
    pandoc operations in the `PandocPure` monad. See the document
@@ -7660,7 +7669,7 @@ For full documentation, see the [pandoc-lua] man page.
    for more details. (This corresponds to the use of the `--sandbox`
    option on the command line.)
 
-5. Pandoc's parsers can exhibit pathological performance on some
+6. Pandoc's parsers can exhibit pathological performance on some
    corner cases.  It is wise to put any pandoc operations under
    a timeout, to avoid DOS attacks that exploit these issues.
    If you are using the pandoc executable, you can add the
@@ -7670,7 +7679,7 @@ For full documentation, see the [pandoc-lua] man page.
    to pathological performance than the `markdown` parser, so
    it is a better choice when processing untrusted input.
 
-6. The HTML generated by pandoc is not guaranteed to be safe.
+7. The HTML generated by pandoc is not guaranteed to be safe.
    If `raw_html` is enabled for the Markdown input, users can
    inject arbitrary HTML.  Even if `raw_html` is disabled,
    users can include dangerous content in URLs and attributes.