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CVE-2025-62518NVD status: Deferred

tokio-tar: Access of Resource Using Incompatible Type

CVE-2025-62518 is a high-severity access of resource using incompatible type vulnerability in tokio-tar from Astral-sh, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected tokio-tar versions: < 0.5.6. The record does not name a fixed version, so check the vendor advisory. 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. Check which version of tokio-tar you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. 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
Astral-shtokio-tar< 0.5.6Not 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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
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
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N. Scored by CNA (github.com).

Official description

astral-tokio-tar is a tar archive reading/writing library for async Rust. Versions of astral-tokio-tar prior to 0.5.6 contain a boundary parsing vulnerability that allows attackers to smuggle additional archive entries by exploiting inconsistent PAX/ustar header handling. When processing archives with PAX-extended headers containing size overrides, the parser incorrectly advances stream position based on ustar header size (often zero) instead of the PAX-specified size, causing it to interpret file content as legitimate tar headers. This issue has been patched in version 0.5.6. There are no workarounds.

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

The underlying weakness: Access of Resource Using Incompatible Type

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

More Access of Resource Using Incompatible Type vulnerabilities (CWE-843)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Access of Resource Using Incompatible Type vulnerabilities

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