Answer in brief
CVE-2026-12539 records a Medium severity (CVSS 5.7) vulnerability in Docker Sandboxes ICMP egress restriction bypass after daemon restart. The current sources do not mark it as known exploited. The current feed maps Docker/Docker Sandboxes (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Docker/Docker Sandboxes (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Docker/Docker Sandboxesgeneric | >=0.14.0 <0.33.0 | 0.33.0 |
Published upstream
Jun 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 22, 2026
Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. A workload inside a sandbox, which the threat model treats as untrusted, can therefore defeat the documented ICMP egress block to perform network reconnaissance and exfiltrate data over an ICMP covert channel, regardless of the configured allowlist.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-12539 records a Medium severity (CVSS 5.7) vulnerability in Docker Sandboxes ICMP egress restriction bypass after daemon restart. The current sources do not mark it as known exploited. The current feed maps Docker/Docker Sandboxes (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Docker/Docker Sandboxes (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Docker/Docker Sandboxesgeneric | >=0.14.0 <0.33.0 | 0.33.0 |
Published upstream
Jun 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 22, 2026
Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. A workload inside a sandbox, which the threat model treats as untrusted, can therefore defeat the documented ICMP egress block to perform network reconnaissance and exfiltrate data over an ICMP covert channel, regardless of the configured allowlist.
Quoted source text, attributed separately from HOL analysis.