CVE-2026-34783 | Ferret has a Path Traversal in IO::FS::WRITE allows arbitrary file write when scraping malicious websites

Exp

Ferret is a declarative system for working with web data. Prior to 2.0.0-alpha.4, a path traversal vulnerability in Ferret's IO::FS::WRITE standard library function allows a malicious website to write arbitrary files to the filesystem of the machine running Ferret. When an operator scrapes a website that returns filenames containing ../ sequences, and uses those filenames to construct output paths (a standard scraping pattern), the attacker controls both the destination path and the file content. This can lead to remote code execution via cron jobs, SSH authorized_keys, shell profiles, or web shells. This vulnerability is fixed in 2.0.0-alpha.4.

Published: 2026-04-06 Last update: 2026-04-14 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-34783 is rated High Exploit Risk (61.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.51%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-34783

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-34783

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.20% 0.51% +0.31%
2 2026-05-18 0.14% 0.20% +0.07%
3 2026-04-15 — 0.14% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-34783

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.2 [email protected]

Weakness enumeration for CVE-2026-34783

GitHub Security Advisory for CVE-2026-34783

GHSA-j6v5-g24h-vg4j · Severity: high · Ecosystem: go — Ferret: Path Traversal in IO::FS::WRITE allows arbitrary file write when scraping malicious websites

Affected software / configurations for CVE-2026-34783

Vendor Product Version Raw CPE
montferret ferret < 2.0.0 cpe:2.3:a:montferret:ferret:*:*:*:*:*:go:*:*
montferret ferret 2.0.0 cpe:2.3:a:montferret:ferret:2.0.0:alpha1:*:*:*:go:*:*
montferret ferret 2.0.0 cpe:2.3:a:montferret:ferret:2.0.0:alpha2:*:*:*:go:*:*
montferret ferret 2.0.0 cpe:2.3:a:montferret:ferret:2.0.0:alpha3:*:*:*:go:*:*

References for CVE-2026-34783

cvelogic Threat Intelligence