CVE-2024-21626: runc container breakout through process.cwd trickery and leaked fds
Vulnerability summary
CVE-2024-21626 is a high (CVSS 8.6) vulnerability in fedoraproject fedora. EPSS estimates a 18.92% chance of exploitation in the next 30 days, higher than 97.3% of scored vulnerabilities. 3 public exploits are recorded.
Weaponized exploit (Metasploit, 31-01-2024)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 5 · Related 39Timeline
- 31-01-2024PublishedVulnerability first disclosed.
- 17-09-2026Last modifiedVulnerability information updated.
Description
runc is a CLI tool for spawning and running containers on Linux according to the OCI specification. In runc 1.1.11 and earlier, due to an internal file descriptor leak, an attacker could cause a newly-spawned container process (from runc exec) to have a working directory in the host filesystem namespace, allowing for a container escape by giving access to the host filesystem ("attack 2"). The same attack could be used by a malicious image to allow a container process to gain access to the host filesystem through runc run ("attack 1"). Variants of attacks 1 and 2 could be also be used to overwrite semi-arbitrary host binaries, allowing for complete container escapes ("attack 3a" and "attack 3b"). runc 1.1.12 includes patches for this issue.
CVSS metrics
9 scores · 9 sources · 1 version- OSV · Red hatEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · WolfiEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · GoEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · ChainguardEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- NVDNIST8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- OSV · AlpineEcosystem advisory · calculated8.6HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS trend
Probability
18.92%
Chance of exploitation in the next 30 days
Percentile
97%
Versus all other CVEs
30-day change
No change 0.00 pp
From 18.92% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
3 foundRunc
Maturity: poc
Exploit Reference (packetstormsecurity.com)
Maturity: unknown
runc (docker) File Descriptor Leak Privilege Escalation
exploit/linux/local/runc_cwd_priv_esc
Maturity: weaponized
Weaknesses
CWE · root cause- CWE-403Exposure of File Descriptor to Unintended Control SphereA process does not close sensitive file descriptors before invoking a child process, which allows the child to perform unauthorized I/O operations using those descriptors.
- CWE-668Exposure of Resource to Wrong SphereThe product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.
- CWE-200Exposure of Sensitive Information to an Unauthorized ActorThe product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
Affected systems
Known conditions: local access, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
Redhat80 products
- aardvark-dns< 2:1.7.0-1.module+el8.9.0+21243+a586538b | < 2:1.0.1-28.module+el8.6.0+21254+7ef668f8 | < 2:1.5.0-2.module+el8.8.0+21265+93802b02 | < 2:1.0.1-40.module+el8.6.0+21266+3e24c7b3
- buildah< 1:1.31.3-3.module+el8.9.0+21243+a586538b | < 1:1.24.2-3.module+el8.6.0+21254+7ef668f8 | < 0:1.11.6-8.module+el8.2.0+21264+96602818 | < 1:1.29.2-1.module+el8.8.0+21265+93802b02 | < 0:1.19.9-1.module+el8.4.0+21078+a96cfbf6 | < 1:1.26.2-1.module+el8.6.0+21266+3e24c7b3
- buildah-debuginfo< 1:1.31.3-3.module+el8.9.0+21243+a586538b | < 1:1.24.2-3.module+el8.6.0+21254+7ef668f8 | < 0:1.11.6-8.module+el8.2.0+21264+96602818 | < 1:1.29.2-1.module+el8.8.0+21265+93802b02 | < 0:1.19.9-1.module+el8.4.0+21078+a96cfbf6 | < 1:1.26.2-1.module+el8.6.0+21266+3e24c7b3
- buildah-debugsource< 1:1.31.3-3.module+el8.9.0+21243+a586538b | < 1:1.24.2-3.module+el8.6.0+21254+7ef668f8 | < 0:1.11.6-8.module+el8.2.0+21264+96602818 | < 1:1.29.2-1.module+el8.8.0+21265+93802b02 | < 0:1.19.9-1.module+el8.4.0+21078+a96cfbf6 | < 1:1.26.2-1.module+el8.6.0+21266+3e24c7b3
- buildah-tests< 1:1.31.3-3.module+el8.9.0+21243+a586538b | < 1:1.24.2-3.module+el8.6.0+21254+7ef668f8 | < 0:1.11.6-8.module+el8.2.0+21264+96602818 | < 1:1.29.2-1.module+el8.8.0+21265+93802b02 | < 0:1.19.9-1.module+el8.4.0+21078+a96cfbf6 | < 1:1.26.2-1.module+el8.6.0+21266+3e24c7b3
Chainguard54 products
- buildkitd< 0.12.5-r1
- cadvisor< 0.48.1-r4
- ctop< 0.7.7-r13
- docker< 25.0.2-r0
- docker-config-mirror-gcr< 25.0.2-r0
Wolfi54 products
- buildkitd< 0.12.5-r1
- cadvisor< 0.48.1-r4
- ctop< 0.7.7-r13
- docker< 25.0.2-r0
- docker-config-mirror-gcr< 25.0.2-r0
Opensuse5 products
- crun&distro=openSUSE Tumbleweed< 1.14.4-1.1
- runc&distro=openSUSE Leap 15.5< 1.1.11-150000.58.1 | < 1.1.12-150000.61.2
- runc&distro=openSUSE Leap Micro 5.3< 1.1.11-150000.58.1 | < 1.1.12-150000.61.2
- runc&distro=openSUSE Leap Micro 5.4< 1.1.11-150000.58.1 | < 1.1.12-150000.61.2
- runc&distro=openSUSE Tumbleweed< 1.1.12-1.1
Alpine1 product
- runc< 1.1.12-r0
Debian1 product
- runc< 1.0.0~rc93+ds1-5+deb11u3 | < 1.1.5+ds1-1+deb12u1 | < 1.1.12+ds1-1
Fedoraproject1 product
- fedoraEOL39
Github.com/opencontainers1 product
- runc≥ 1.0.0-rc93, < 1.1.12
Linuxfoundation1 product
- runc< 1.1.12
Opencontainers1 product
- runc≥ v1.0.0-rc93, < 1.1.12
Ubuntu1 product
- runc< 1.1.4-0ubuntu1~18.04.2+esm1 | < 1.1.7-0ubuntu1~20.04.2 | < 1.1.7-0ubuntu1~22.04.2
11 vendors · 200 products · Showing 200 of 231
References
89 links- github.com/opencontainers/runc/security/advisories/GHSA-xr7r-f8xq-vfvvX Refsource CONFIRMARTICLEREPORTAdvisoryWEBExploitVendor Advisory
- github.com/opencontainers/runc/commit/02120488a4c0fc487d1ed2867e901eeed7ce8ecfX Refsource MISCFIXWEBPatch
- packetstormsecurity.com/files/176993/runc-1.1.11-File-Descriptor-Leak-Privilege-Escalation.htmlWEBExploitThird Party AdvisoryVDB Entry