This project might be open to known security vulnerabilities, which can be prevented by tightening the version range of affected dependencies. Find detailed information at the bottom.
When unpacking a tarball that contains a symlink the tar crate may create
directories outside of the directory it's supposed to unpack into.
The function errors when it's trying to create a file, but the folders are
already created at this point.
use std::{io, io::Result};
use tar::{Archive, Builder, EntryType, Header};
fn main() -> Result<()> {
let mut buf = Vec::new();
{
let mut builder = Builder::new(&mut buf);
// symlink: parent -> ..
let mut header = Header::new_gnu();
header.set_path("symlink")?;
header.set_link_name("..")?;
header.set_entry_type(EntryType::Symlink);
header.set_size(0);
header.set_cksum();
builder.append(&header, io::empty())?;
// file: symlink/exploit/foo/bar
let mut header = Header::new_gnu();
header.set_path("symlink/exploit/foo/bar")?;
header.set_size(0);
header.set_cksum();
builder.append(&header, io::empty())?;
builder.finish()?;
};
Archive::new(&*buf).unpack("demo")
}
This has been fixed in https://github.com/alexcrichton/tar-rs/pull/259 and is
published as tar 0.4.36. Thanks to Martin Michaelis (@mgjm) for discovering
and reporting this, and Nikhil Benesch (@benesch) for the fix!
regex: Regexes with large repetitions on empty sub-expressions take a very long time to parse
The Rust Security Response WG was notified that the regex crate did not
properly limit the complexity of the regular expressions (regex) it parses. An
attacker could use this security issue to perform a denial of service, by
sending a specially crafted regex to a service accepting untrusted regexes. No
known vulnerability is present when parsing untrusted input with trusted
regexes.
This issue has been assigned CVE-2022-24713. The severity of this vulnerability
is "high" when the regex crate is used to parse untrusted regexes. Other uses
of the regex crate are not affected by this vulnerability.
Overview
The regex crate features built-in mitigations to prevent denial of service
attacks caused by untrusted regexes, or untrusted input matched by trusted
regexes. Those (tunable) mitigations already provide sane defaults to prevent
attacks. This guarantee is documented and it's considered part of the crate's
API.
Unfortunately a bug was discovered in the mitigations designed to prevent
untrusted regexes to take an arbitrary amount of time during parsing, and it's
possible to craft regexes that bypass such mitigations. This makes it possible
to perform denial of service attacks by sending specially crafted regexes to
services accepting user-controlled, untrusted regexes.
Affected versions
All versions of the regex crate before or equal to 1.5.4 are affected by this
issue. The fix is include starting from regex 1.5.5.
Mitigations
We recommend everyone accepting user-controlled regexes to upgrade immediately
to the latest version of the regex crate.
Unfortunately there is no fixed set of problematic regexes, as there are
practically infinite regexes that could be crafted to exploit this
vulnerability. Because of this, we do not recommend denying known problematic
regexes.
Acknowledgements
We want to thank Addison Crump for responsibly disclosing this to us according
to the Rust security policy, and for helping review the fix.
We also want to thank Andrew Gallant for developing the fix, and Pietro Albini
for coordinating the disclosure and writing this advisory.
Affected versions of this crate allowed the bytes { and \xa0 to appear
unquoted and unescaped in command arguments.
If the output of quote or join is passed to a shell, then what should be a
single command argument could be interpreted as multiple arguments.
This does not directly allow arbitrary command execution (you can't inject a
command substitution or similar). But depending on the command you're running,
being able to inject multiple arguments where only one is expected could lead
to undesired consequences, potentially including arbitrary command execution.
The flaw was corrected in version 1.2.1 by escaping additional characters.
Updating to 1.3.0 is recommended, but 1.2.1 offers a more minimal fix if
desired.
Workaround: Check for the bytes { and \xa0 in quote/join input or
output.
(Note: { is problematic because it is used for glob expansion. \xa0 is
problematic because it's treated as a word separator in specific
environments.)
Issue 2: Dangerous API w.r.t. nul bytes
Version 1.3.0 deprecates the quote and join APIs in favor of try_quote
and try_join, which behave the same except that they have Result return
type, returning Err if the input contains nul bytes.
Strings containing nul bytes generally cannot be used in Unix command arguments
or environment variables, and most shells cannot handle nul bytes even
internally. If you try to pass one anyway, then the results might be
security-sensitive in uncommon scenarios. More details here.
Due to the low severity, the behavior of the original quote and join APIs
has not changed; they continue to allow nuls.
Workaround: Manually check for nul bytes in quote/join input or output.
Issue 3: Lack of documentation for interactive shell risks
The quote family of functions does not and cannot escape control characters.
With non-interactive shells this is perfectly safe, as control characters have
no special effect. But if you writing directly to the standard input of an
interactive shell (or through a pty), then control characters can cause
misbehavior including arbitrary command injection.
This is essentially unfixable, and has not been patched. But as of version
1.3.0, documentation has been added.
Future versions of shlex may add API variants that avoid the issue at the
cost of reduced portability.
