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Fencer Intel
medium 6.5

CVE-2024-43806 json

`rustix::fs::Dir` iterator with the `linux_raw` backend can cause memory explosion

published 3y ago modified 2mo ago also GHSA-c827-hfw6-qwvm , EUVD-2023-2715

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 41%
public exploits
0
none known

Summary

Rustix is a set of safe Rust bindings to POSIX-ish APIs. When using `rustix::fs::Dir` using the `linux_raw` backend, it's possible for the iterator to "get stuck" when an IO error is encountered. Combined with a memory over-allocation issue in `rustix::fs::Dir::read_more`, this can cause quick and unbounded memory explosion (gigabytes in a few seconds if used on a hot path) and eventually lead to an OOM crash of the application. The symptoms were initially discovered in https://github.com/imsnif/bandwhich/issues/284. That post has lots of details of our investigation. Full details can be read on the GHSA-c827-hfw6-qwvm repo advisory. If a program tries to access a directory with its file descriptor after the file has been unlinked (or any other action that leaves the `Dir` iterator in the stuck state), and the implementation does not break after seeing an error, it can cause a memory explosion. As an example, Linux's various virtual file systems (e.g. `/proc`, `/sys`) can contain directories that spontaneously pop in and out of existence. Attempting to iterate over them using `rustix::fs::Dir` directly or indirectly (e.g. with the `procfs` crate) can trigger this fault condition if the implementation decides to continue on errors. An attacker knowledgeable about the implementation details of a vulnerable target can therefore try to trigger this fault condition via any one or a combination of several available APIs. If successful, the application host will quickly run out of memory, after which the application will likely be terminated by an OOM killer, leading to denial of service. This issue has been addressed in release versions 0.35.15, 0.36.16, 0.37.25, and 0.38.19. Users are advised to upgrade. There are no known workarounds for this issue.

Patch / fix

  • crates.io rustix 0.35.15, 0.36.16, 0.37.25, 0.38.19
  • bytecodealliance rustix 0.35.15, 0.36.16, 0.37.25, 0.38.19
  • rust-rustix Debian 14, Debian 13 0.38.21-1

debian advisories DEBIAN-CVE-2024-43806

  • sccache SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Development Tools 15 SP7 0.16.0~0-150600.10.11.1
  • librsvg SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 2.60.2-160000.1.1
  • librsvg SLE Micro 5.5, SLE Micro 5.4, SLE Micro 5.3 2.52.12-150400.3.9.1
  • rust-keylime Linux Micro 6.1 0.2.8+12-slfo.1.1_1.1
  • rust-keylime SLE Micro 5.5 0.2.7+141-150500.3.5.1
  • rust-keylime SLE Micro 5.4 0.2.7+141-150400.3.5.1
  • rust-keylime SLE Micro 5.3 0.2.7+141-150400.3.7.1
  • rust-keylime Linux Micro 6.0 0.2.6+13-1.1

suse advisories SUSE-SU-2026:3022-1SUSE-SU-2026:20755-1SUSE-SU-2026:20910-1SUSE-SU-2025:4411-1SUSE-SU-2025:20858-1SUSE-SU-2025:02811-1

  • librsvg openSUSE Leap 16.0 2.60.2-160000.1.1
  • rust-keylime openSUSE Tumbleweed 0.2.7+70-2.1
  • rage-encryption openSUSE Tumbleweed 0.10.0+0-3.1
  • 389-ds openSUSE Tumbleweed 3.1.1~git13.a9c7ff9-1.1

opensuse advisories openSUSE-SU-2026:20396-1openSUSE-SU-2025:15294-1openSUSE-SU-2024:14354-1openSUSE-SU-2024:14306-1

  • cloud-hypervisor CBL-Mariner 2.0 32.0-7
  • rust CBL-Mariner 2.0 1.72.0-9
  • virtiofsd CBL-Mariner 2.0, Azure Linux 3.0 1.8.0-3
  • kata-containers-cc CBL-Mariner 2.0 3.2.0.azl2-7
  • flux Azure Linux 3.0 0.194.5-4
  • kata-containers-cc Azure Linux 3.0 3.2.0.azl4-1
  • kata-containers Azure Linux 3.0 3.2.0.azl4-1

azure linux advisories AZL-48300AZL-48304AZL-48312AZL-48318AZL-48324AZL-48327

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
2y ago

Exploit prediction

0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
crates.io rustix
>=0.35.11, <0.35.15
>=0.36.0, <0.36.16
>=0.37.0, <0.37.25
>=0.38.0, <0.38.19
0.35.15
0.36.16
0.37.25
0.38.19

Affected products

  • bytecodealliance rustix

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.