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NVD / CVE Program· CNA Docker

CVE-2026-77179: Docker Sandboxes guest can write arbitrary macOS host files via a symlink in the virtio-fs stored-path fallback

CriticalCVSS 9.4 · v4.0—Proof of concept Fix available

Noroxi assessment

Priority: Monitor (action score 37/100)

  • Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Docker Docker Sandboxes 0.42.0.

Low priority for now. Upgrade to Docker Docker Sandboxes 0.42.0 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

On macOS, the virtio-fs host server used by Docker Sandboxes improperly follows symlinks when reopening an unlinked file from a stored path. A malicious guest can replace a parent directory with a symlink, escape the shared workspace, and read or modify arbitrary host files as the VMM user, potentially achieving host code execution.

Published
Sep 15, 2026
Updated
Sep 16, 2026
EPSS
0.1% · 9th percentile

Report tools

JSON

Action score

37

Monitor

Low priority for now.

CVSS
37 / 40 · 9.4 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · Docker
9.4
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-77179

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Docker). Independent of NVD's CPE analysis and usually ahead of it.

  • Docker Docker Sandboxes

    • 0.28.0 and later · before 0.42.0affected · semver

Same product

docker: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-79994Docker Sandboxes UDS forwarder can reach arbitrary host Unix sockets through a symlink race
    34Monitor
  • CVE-2026-103916Docker Sandboxes sbx cp follows workspace symlinks outside the authorized host directory
    33Monitor
  • CVE-2026-126329Docker Sandboxes privilege escalation through untrusted state directories
    29Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-12539Jun 18, 2026 · Docker Sandboxes ICMP egress restriction bypass after daemon restart
    22Monitor
  • ← EarlierCVE-2026-18171Aug 12, 2026 · Docker Sandboxes read-only runtime mount writable through its shared-export alias
    22Monitor
  • Later →CVE-2026-101998Oct 8, 2026 · Fail-open response masking in Docker Sandboxes can expose proxy-managed credentials
    23Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Docker Docker Sandboxes0.42.0Vendor (CNA)

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:02026-09-18

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. First PoC+3 d
  3. TodayNov 12, 2026+58 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-10391649 days apartDocker Sandboxes sbx cp follows workspace symlinks outside the authorized host directory
    33Monitor

Bug bounty scope

The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.

Not on record for this CVE: patch commit or PR link.

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-59 · Improper Link Resolution Before File Access ('Link Following')

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records