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CVE Record

CVE-2026-34430: ByteDance DeerFlow LocalSandboxProvider Host Bash Escape

ByteDance DeerFlow versions prior to commit 92c7a20 contain a sandbox escape vulnerability in bash tool handling that allows attackers to execute arbitrary commands on the host system by bypassing regex-based validation using shell features such as directory changes and relative paths. Attackers can exploit the incomplete shell semantics modeling to read and modify files outside the sandbox boundary and achieve arbitrary command execution through subprocess invocation with shell interpretation enabled.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A flaw in DeerFlow’s local sandbox can let untrusted bash activity escape its intended boundary and run commands on the host. Successful exploitation could expose or alter host files and disrupt services. The supplied CVSS score is 8.8, reflecting potentially severe confidentiality, integrity, and availability impact.

Executive priority

Treat this as a high-priority remediation for exposed or untrusted-input DeerFlow deployments. A sandbox escape undermines a primary security boundary and may permit host compromise. Patch promptly, reduce bash-tool exposure during remediation, and investigate suspicious host activity. Emergency incident response is not justified solely by the supplied sources because active exploitation is unconfirmed.

Technical view

DeerFlow before commit 92c7a20 incompletely validates bash commands using regular expressions. Shell semantics, including directory changes and relative paths, can bypass those checks. Because subprocess execution enables shell interpretation, escaped commands may access files outside LocalSandboxProvider and execute on the host. The supplied vector indicates network access, low complexity, no privileges, and required user interaction.

Likely exposure

Prioritize DeerFlow deployments using LocalSandboxProvider that do not contain commit 92c7a20, particularly where untrusted input can reach bash tool handling. The bundle does not identify a fixed release number, and its structured affected-version entry is unclear, so exposure should be confirmed through commit ancestry and vendor release guidance.

Exploitation context

The supplied record does not list this CVE in KEV and provides no cited evidence of active exploitation. Its CVSS assessment indicates low attack complexity and no required privileges, but user interaction is required. Public technical references describe the weakness and patch; the bundle does not establish whether functional exploit code is publicly available.

Researcher notes

The weakness is classified as CWE-184: incomplete handling of disallowed inputs. Regex validation failed to model full shell behavior, while shell-enabled subprocess execution preserved dangerous interpretation. Commit 92c7a20 is the concrete remediation reference. Exact vulnerable release ranges and exploitation prevalence remain insufficiently specified in the supplied bundle.

Mitigation direction

  • Upgrade to a DeerFlow release containing commit 92c7a20 or apply the referenced patch.
  • Until patched, prevent untrusted input from reaching DeerFlow bash tool handling.
  • Restrict DeerFlow host permissions and accessible files to reduce escape impact.
  • Check ByteDance guidance for a fixed release designation and additional mitigations.

Validation and detection

  • Determine whether each DeerFlow deployment uses LocalSandboxProvider and exposes bash tools.
  • Verify deployed source includes commit 92c7a20 or a vendor-confirmed equivalent fix.
  • Review host telemetry for unexpected subprocess execution or access outside sandbox directories.
  • Test the fix safely using non-destructive boundary checks in an isolated environment.
Prepared
Confidence
high
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-184: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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description · low confidence lookup

Privilege behavior lookup

The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2026-34430 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
8.8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
3Timeline events
1ADP providers
4Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H2.85.9VulnCheck
8.6CVSS 4.0HighCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——VulnCheck

Vulnerability scoring details

Base CVSS 4.0 score

8.6High
CVSS 4.0 vector shape for CVE-2026-34430Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Bytedance Inc.DeerFlow0unaffected
Weakness

CWE details

CWE-184

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-184 · source CWE mapping

Incomplete List of Disallowed Inputs

Incomplete List of Disallowed Inputs represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

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