CVE-2026-104025 — Path traversal in PeaZip object preview allows execution of arbitrary programs via a crafted archive entry name
Path Traversal (CWE-22) in the execute_obj function of the archive object viewer (peach.pas) in PeaZip 11.2.0 and earlier on Windows allows an attacker who convinces a victim to preview an entry of a crafted archive via the "Preview with... -> Associated application" action (Shift+Ctrl+O) to execute an arbitrary program already present on the victim's system, with no warning dialog. The function validates only outname (PeaZip's own temporary directory) with checkfiledirname, while the string actually executed is the concatenation outname+tempstring; tempstring is taken verbatim from the archive entry name (StringGridList.Cells[12,...]) and is never validated. checkfiledirname (list_utils.pas) rejects control and reserved characters in the file name but performs no ".." path-containment check, so an entry named ../../../../Windows/System32/calc.exe escapes the extraction directory and is passed to cp_open -> ShellExecuteW; the extracting backend (7-Zip) strips the traversal while the opener does not. In addition, the SECEXTCONST dangerous-extension confirmation prompt is implemented only in the double-click handler (grid_obj_open) and not on this preview route, so an executable inside an archive reaches ShellExecuteW unannounced, and where the prompt does fire it names the entry's display name rather than the resolved path that will run. Arbitrary code execution was demonstrated with a proof of concept against official PeaZip builds, confirmed on two archive formats (.zip and .tar) to show the defect is in PeaZip's own path handling and not in a single format parser.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (PeaZip PeaZip).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Exploitation requires user interaction: tighten email/web filtering and warn affected users.
- Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.4 | CVSS 4.0 | High | — | — | 4daa8cea-433a-44bd-9456-53b127fc289a via NIST National Vulnerability Database |
| 8.4 | CVSS 4.0 | High | — | — | Secur0 via CVE Program (cve.org) e CISA ADP |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/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 (score shown at the top: 4daa8cea-433a-44bd-9456-53b127fc289a) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Monitor file creation in web directories and paths with traversal sequences (../).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · peazip/peazip
- SSVC assessment updated
- Record published
- CVSS changed · 8.4
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× References added · Oct 15, 2026 – Oct 15, 2026
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-104024 Incomplete dangerous-extension list in PeaZip object open allows execution of a program or command from a crafted archive entry without confirmation 3h
- High CVE-2026-105050 PeaZip before 11.3.0, in a non-default configuration, is vulnerable to OS command… 12d
- High CVE-2026-102514 Out-of-bounds write in PeaZip PEA extractor allows code execution via a crafted .pea archive 13d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-104025 is "Path traversal in PeaZip object preview allows execution of arbitrary programs via a crafted archive entry name", rated High. It affects PeaZip (PeaZip); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.4 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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