docker-socket-proxy through 0.5.0 Insufficient Access Control Granularity Exposes Container Filesystems

published 2026-08-22 2 mo ago modified 2026-10-12 28 d ago also EUVD-2026-64603

cvss: 7.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 23%
public exploits: 0; none known

docker-socket-proxy fails to properly gate read endpoints in the /containers Docker API namespace when the CONTAINERS environment variable is set. Attackers can use GET requests to /containers/{id}/archive, /containers/{id}/export, /containers/{id}/logs, and /containers/{id}/top to read arbitrary files and download entire container filesystems as tar archives.

Patch / fix

links 1

github.com/Tecnativa/docker-socket-proxy#183 pull request

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-26)

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/Tecnativa/docker-socket-proxy/issues/182 referenced PoC, tagged "exploit" by a source, unverified
gist.github.com https://gist.github.com/nedlir/e4f52f88a757f02c67db1fd5dd70d732 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.3	CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
CNA	3.1	7.4	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
CNA	4.0	8.3	CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

Tecnativa docker-socket-proxy

Classification

Weakness

CWE-1220 Insufficient Granularity of Access Control

References

github.com /Tecnativa/docker-socket-proxy/pull/183
issue-tracking, patch
github.com /Tecnativa/docker-socket-proxy/issues/182
issue-tracking, exploit
gist.github.com /nedlir/e4f52f88a757f02c67db1fd5dd70d732
exploit
github.com /Tecnativa/docker-socket-proxy
product
github.com /Tecnativa/docker-socket-proxy/blob/v0.5.0/haproxy.cfg#L49-L61
technical-description
vulncheck.com /advisories/docker-socket-proxy-through-insufficient-access-control-granularity-exposes-container-filesystems
third-party-advisory

Sources

CVE List CVE-2026-78122
NVD CVE-2026-78122

Fencer Vulns 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.

Summary