Security readout for executives and security teams
Plain-English summary
CVE-2026-27117 is a Zip Slip path traversal issue in bit7z before 4.0.11. If an application extracts an attacker-supplied archive with vulnerable bit7z, files may be written outside the intended folder. Business impact depends on what the extracting process can overwrite, such as configuration files, application files, or other sensitive data.
Executive priority
Treat as a targeted remediation item for systems handling untrusted archives. Prioritize internet-facing upload services, automated ingestion pipelines, and privileged backend processors. The issue is not reported as actively exploited in the provided sources, but arbitrary file write can create meaningful integrity risk.
Technical view
bit7z archive extraction before 4.0.11 insufficiently validates archive entry paths. The advisory describes relative path traversal, absolute path traversal, and symbolic link traversal. Exploitation requires a malicious archive to be processed by an application using bit7z. Impact is arbitrary file write with the extracting process privileges; the advisory states it does not directly allow file reading.
Likely exposure
Exposure is limited to products or internal tools that embed bit7z versions earlier than 4.0.11 and extract untrusted archives. Systems that only create archives, or never process attacker-controlled archive content, have lower practical exposure.
Exploitation context
The CVSS vector indicates local attack vector and user interaction required. No KEV listing or provided source states active exploitation. Risk rises where archive extraction is automated for customer uploads, email attachments, CI artifacts, or partner-supplied files.
Researcher notes
Focus assessment on embedded library usage, not just standalone packages. The key condition is extraction of attacker-controlled archives through bit7z before 4.0.11. Validate protections against relative, absolute, and symlink traversal. Avoid assuming confidentiality impact unless the consuming application exposes extracted content or follows attacker-created links.
Mitigation direction
- Upgrade bit7z to version 4.0.11 or later.
- Validate each archive entry destination path before writing files.
- Run archive extraction with least privilege.
- Extract untrusted archives inside a sandboxed directory.
- Review vendor advisory and release notes for implementation-specific guidance.
Validation and detection
- Inventory applications and builds that include bit7z.
- Confirm deployed bit7z versions are 4.0.11 or later.
- Identify workflows extracting untrusted or external archives.
- Review extraction code for canonical path validation before file writes.
- Check runtime permissions for processes performing extraction.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-22: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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.
Open ATT&CK lookupCWE-23: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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.
Open ATT&CK lookupCWE-36: 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.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-27117 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/rikyoz/bit7z/security/advisories/GHSA-qvjh-hhw4-3gx9CVE reference · x_refsource_CONFIRM
- https://github.com/rikyoz/bit7z/commit/31763da9a3e41a199c141c8d71f6c11de24b45cfCVE reference · x_refsource_MISC
- https://github.com/rikyoz/bit7z/commit/9e020483eefa5825ec9310b1d869933d4f77f969CVE reference · x_refsource_MISC
- https://github.com/rikyoz/bit7z/releases/tag/v4.0.11CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Relative Path Traversal
Relative Path Traversal represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Absolute Path Traversal
Absolute Path Traversal represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.