CyberSecBulletin
CVE-2023-38497NVD status: Modified

cargo: Incorrect Permission Assignment for Critical Resource

Published Updated By the CyberSecBulletin desk

CVE-2023-38497 is a high-severity incorrect permission assignment for critical resource vulnerability in cargo from Rust-lang, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. The record lists version 0.72.2 as the first without the flaw, so updating cargo to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.7% chance of exploitation within 30 days, higher than 54% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update cargo to 0.72.2 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Rust-langcargo< 0.72.2; before 0.72.20.72.2
Fedora ProjectFedora38Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.9HighCNA (github.com)
CVSS 3.17.3HighNVD

Official description

Cargo downloads the Rust project’s dependencies and compiles the project. Cargo prior to version 0.72.2, bundled with Rust prior to version 1.71.1, did not respect the umask when extracting crate archives on UNIX-like systems. If the user downloaded a crate containing files writeable by any local user, another local user could exploit this to change the source code compiled and executed by the current user. To prevent existing cached extractions from being exploitable, the Cargo binary version 0.72.2 included in Rust 1.71.1 or later will purge caches generated by older Cargo versions automatically. As a workaround, configure one's system to prevent other local users from accessing the Cargo directory, usually located in `~/.cargo`.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Permission Assignment for Critical Resource

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

How developers prevent this class of flaw

  • When using a critical resource such as a configuration file, check to see if the resource has insecure permissions (such as being modifiable by any regular user), and generate an error or even exit the software if there is a possibility that the resource could have been modified by an unauthorized party.
  • Divide the software into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully defining distinct user groups, privileges, and/or roles. Map these against data, functionality, and the related resources. Then set the permissions accordingly. This will allow you to maintain more fine-grained control over your resources.
  • During program startup, explicitly set the default permissions or umask to the most restrictive setting possible. Also set the appropriate permissions during program installation. This will prevent you from inheriting insecure permissions from any user who installs or runs the program.

More Incorrect Permission Assignment for Critical Resource vulnerabilities (CWE-732)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in cargo

All cargo vulnerabilities

Recent Incorrect Permission Assignment for Critical Resource vulnerabilities

Spotted an error? Tell us.