GHSA-2hvr-h6gw-qrxp CVE-2022-36114
Cargo extracting malicious crates can fill the file system
- Severity
- 4.2 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 0.95%
- Chance of exploitation in the next 30 days. Higher than 61.09% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-400 Uncontrolled Resource Consumption
- Fix
0.65.0- Upgrade cargo to this version or later
Description
The Rust Security Response WG was notified that Cargo did not prevent extracting some malformed packages downloaded from alternate registries. An attacker able to upload packages to an alternate registry could fill the file system when Cargo downloaded the package.
The severity of this vulnerability is "low" for users of alternate registries. Users relying on crates.io are not affected.
Note that by design Cargo allows code execution at build time, due to build scripts and procedural macros. The vulnerabilities in this advisory allow performing a subset of the possible damage in a harder to track down way. Your dependencies must still be trusted if you want to be protected from attacks, as it's possible to perform the same attacks with build scripts and procedural macros.
Disk space exaustion
It was discovered that Cargo did not limit the amount of data extracted from compressed archives. An attacker could upload to an alternate registry a specially crafted package that extracts way more data than its size (also known as a "zip bomb"), exhausting the disk space on the machine using Cargo to download the package.
Affected versions
The vulnerability is present in all versions of Cargo. Rust 1.64, to be released on September 22nd, will include a fix for it.
Since the vulnerability is just a more limited way to accomplish what a malicious build scripts or procedural macros can do, we decided not to publish Rust point releases backporting the security fix. Patch files are available for Rust 1.63.0 are available in the wg-security-response repository for people building their own toolchain.
Mitigations
We recommend users of alternate registries to excercise care in which package they download, by only including trusted dependencies in their projects. Please note that even with these vulnerabilities fixed, by design Cargo allows arbitrary code execution at build time thanks to build scripts and procedural macros: a malicious dependency will be able to cause damage regardless of these vulnerabilities.
crates.io implemented server-side checks to reject these kinds of packages years ago, and there are no packages on crates.io exploiting these vulnerabilities. crates.io users still need to excercise care in choosing their dependencies though, as the same concerns about build scripts and procedural macros apply here.
Acknowledgements
We want to thank Ori Hollander from JFrog Security Research for responsibly disclosing this to us according to the Rust security policy.
We also want to thank Josh Triplett for developing the fixes, Weihang Lo for developing the tests, and Pietro Albini for writing this advisory. The disclosure was coordinated by Pietro Albini and Josh Stone.
Affected versions
crates.io
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
cargo crates.io → 0.65.0
- cargo
cargo update -p cargo --precise 0.65.0
Severity breakdown
CVSS 3.1 4.2
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- High
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Weakness
CWE-400: Uncontrolled Resource Consumption
The product does not properly control the allocation and maintenance of a limited resource.
How to prevent it
- Architecture and Design: Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
- Architecture and Design: Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed. The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question. The second solution is simply difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
- Architecture and Design: Ensure that protocols have specific limits of scale placed on them.
- Implementation: Ensure that all failures in resource allocation place the system into a safe posture.
References
Advisories
Packages
Other links
- github.com/rust-lang/cargo/security/advisories/GHSA-2hvr-h6gw-qrxp
- github.com/rust-lang/cargo/commit/2b68d3c07a4a056264dc006ecb9f1354a0679cd3
- github.com/rust-lang/cargo/commit/d1f9553c825f6d7481453be8d58d0e7f117988a7
- github.com/rust-lang/cargo/commit/d87d57dbbda61754f4fab0f329a7ac520e062c46
- security.gentoo.org/glsa/202210-09
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-jq42-7mfv-hm57 Cargo crates in third party registries can override the cached source of other crates | Medium | Also affects cargo |
| GHSA-p688-r7jv-fm6f Cargo can be coerced to share credentials between registries | Medium | Also affects cargo |
| GHSA-wrrj-h57r-vx9p Malicious dependencies can inject arbitrary JavaScript into cargo-generated timing reports | Medium | Also affects cargo |
| GHSA-j3xp-wfr4-hx87 Cargo not respecting umask when extracting crate archives | High | Also affects cargo |
| GHSA-r5w3-xm58-jv6j Cargo did not verify SSH host keys | Medium | Also affects cargo |
| GHSA-rfj2-q3h3-hm5j Cargo extracting malicious crates can corrupt arbitrary files | High | Also affects cargo |
| GHSA-9f3p-wvj7-q82x Cargo prior to Rust 1.26.0 may download the wrong dependency | High | Also affects cargo |
| GHSA-cggf-277g-3q54 pypdf has possible large memory usage when parsing page tree | High | Same weakness, CWE-400 |
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