Search for vulnerabilities
Vulnerability details: VCID-us2v-fh9z-aaaa
Vulnerability ID VCID-us2v-fh9z-aaaa
Aliases CVE-2021-43784
GHSA-v95c-p5hm-xq8f
Summary runc is a CLI tool for spawning and running containers on Linux according to the OCI specification. In runc, netlink is used internally as a serialization system for specifying the relevant container configuration to the `C` portion of the code (responsible for the based namespace setup of containers). In all versions of runc prior to 1.0.3, the encoder did not handle the possibility of an integer overflow in the 16-bit length field for the byte array attribute type, meaning that a large enough malicious byte array attribute could result in the length overflowing and the attribute contents being parsed as netlink messages for container configuration. This vulnerability requires the attacker to have some control over the configuration of the container and would allow the attacker to bypass the namespace restrictions of the container by simply adding their own netlink payload which disables all namespaces. The main users impacted are those who allow untrusted images with untrusted configurations to run on their machines (such as with shared cloud infrastructure). runc version 1.0.3 contains a fix for this bug. As a workaround, one may try disallowing untrusted namespace paths from your container. It should be noted that untrusted namespace paths would allow the attacker to disable namespace protections entirely even in the absence of this bug.
Status Published
Exploitability 0.5
Weighted Severity 8.0
Risk 4.0
Affected and Fixed Packages Package Details
Weaknesses (1)
CWE-190 Integer Overflow or Wraparound
System Score Found at
cvssv3 5.0 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43784.json
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0013 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00131 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00141 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.0015 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00163 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00398 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00398 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00398 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00398 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00528 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
epss 0.00817 https://api.first.org/data/v1/epss?cve=CVE-2021-43784
cvssv3.1 6.0 https://bugs.chromium.org/p/project-zero/issues/detail?id=2241
generic_textual MODERATE https://bugs.chromium.org/p/project-zero/issues/detail?id=2241
rhbs low https://bugzilla.redhat.com/show_bug.cgi?id=2029439
cvssv3.1 3.6 https://github.com/opencontainers/runc
generic_textual LOW https://github.com/opencontainers/runc
cvssv3.1 6.0 https://github.com/opencontainers/runc/commit/9c444070ec7bb83995dbc0185da68284da71c554
generic_textual MODERATE https://github.com/opencontainers/runc/commit/9c444070ec7bb83995dbc0185da68284da71c554
cvssv3.1 6.0 https://github.com/opencontainers/runc/commit/d72d057ba794164c3cce9451a00b72a78b25e1ae
generic_textual MODERATE https://github.com/opencontainers/runc/commit/d72d057ba794164c3cce9451a00b72a78b25e1ae
cvssv3.1 6.0 https://github.com/opencontainers/runc/commit/dde509df4e28cec33b3c99c6cda3d4fd5beafc77
generic_textual MODERATE https://github.com/opencontainers/runc/commit/dde509df4e28cec33b3c99c6cda3d4fd5beafc77
cvssv3.1 6.0 https://github.com/opencontainers/runc/commit/f50369af4b571e358f20b139eea52d612eb55eed
generic_textual MODERATE https://github.com/opencontainers/runc/commit/f50369af4b571e358f20b139eea52d612eb55eed
cvssv3.1 6.0 https://github.com/opencontainers/runc/security/advisories/GHSA-v95c-p5hm-xq8f
generic_textual MODERATE https://github.com/opencontainers/runc/security/advisories/GHSA-v95c-p5hm-xq8f
cvssv3.1 6.0 https://lists.debian.org/debian-lts-announce/2021/12/msg00005.html
generic_textual MODERATE https://lists.debian.org/debian-lts-announce/2021/12/msg00005.html
cvssv3.1 8.6 https://lists.debian.org/debian-lts-announce/2024/02/msg00005.html
generic_textual HIGH https://lists.debian.org/debian-lts-announce/2024/02/msg00005.html
cvssv2 6.0 https://nvd.nist.gov/vuln/detail/CVE-2021-43784
cvssv3 5.0 https://nvd.nist.gov/vuln/detail/CVE-2021-43784
cvssv3.1 5.0 https://nvd.nist.gov/vuln/detail/CVE-2021-43784
cvssv3.1 6.0 https://pkg.go.dev/vuln/GO-2022-0274
generic_textual MODERATE https://pkg.go.dev/vuln/GO-2022-0274
archlinux Low https://security.archlinux.org/AVG-2599
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43784.json
https://api.first.org/data/v1/epss?cve=CVE-2021-43784
https://bugs.chromium.org/p/project-zero/issues/detail?id=2241
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43784
https://github.com/opencontainers/runc
https://github.com/opencontainers/runc/commit/9c444070ec7bb83995dbc0185da68284da71c554
https://github.com/opencontainers/runc/commit/d72d057ba794164c3cce9451a00b72a78b25e1ae
https://github.com/opencontainers/runc/commit/dde509df4e28cec33b3c99c6cda3d4fd5beafc77
https://github.com/opencontainers/runc/commit/f50369af4b571e358f20b139eea52d612eb55eed
https://github.com/opencontainers/runc/security/advisories/GHSA-v95c-p5hm-xq8f
https://lists.debian.org/debian-lts-announce/2021/12/msg00005.html
https://lists.debian.org/debian-lts-announce/2024/02/msg00005.html
https://pkg.go.dev/vuln/GO-2022-0274
2029439 https://bugzilla.redhat.com/show_bug.cgi?id=2029439
AVG-2599 https://security.archlinux.org/AVG-2599
cpe:2.3:a:linuxfoundation:runc:*:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:linuxfoundation:runc:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
CVE-2021-43784 https://nvd.nist.gov/vuln/detail/CVE-2021-43784
GLSA-202408-25 https://security.gentoo.org/glsa/202408-25
RHSA-2023:6380 https://access.redhat.com/errata/RHSA-2023:6380
USN-6088-2 https://usn.ubuntu.com/6088-2/
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43784.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://bugs.chromium.org/p/project-zero/issues/detail?id=2241
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N Found at https://github.com/opencontainers/runc
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://github.com/opencontainers/runc/commit/9c444070ec7bb83995dbc0185da68284da71c554
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://github.com/opencontainers/runc/commit/d72d057ba794164c3cce9451a00b72a78b25e1ae
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://github.com/opencontainers/runc/commit/dde509df4e28cec33b3c99c6cda3d4fd5beafc77
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://github.com/opencontainers/runc/commit/f50369af4b571e358f20b139eea52d612eb55eed
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://github.com/opencontainers/runc/security/advisories/GHSA-v95c-p5hm-xq8f
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://lists.debian.org/debian-lts-announce/2021/12/msg00005.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H Found at https://lists.debian.org/debian-lts-announce/2024/02/msg00005.html
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: AV:N/AC:M/Au:S/C:P/I:P/A:P Found at https://nvd.nist.gov/vuln/detail/CVE-2021-43784
Exploitability (E) Access Vector (AV) Access Complexity (AC) Authentication (Au) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

high

functional

unproven

proof_of_concept

not_defined

local

adjacent_network

network

high

medium

low

multiple

single

none

none

partial

complete

none

partial

complete

none

partial

complete
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L Found at https://nvd.nist.gov/vuln/detail/CVE-2021-43784
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L Found at https://nvd.nist.gov/vuln/detail/CVE-2021-43784
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L Found at https://pkg.go.dev/vuln/GO-2022-0274
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.33904
EPSS Score 0.0013
Published At May 15, 2025, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
There are no relevant records.