How severe is CVE-2026-42608?

CVE-2026-42608 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-42608 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42608?

CVE-2026-42608 primarily affects Getgrav Grav. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-42608?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-42608 have an EU (EUVD) identifier?

Yes. CVE-2026-42608 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29066.

When was CVE-2026-42608 published?

CVE-2026-42608 was published on 2026-05-11 and last updated on 2026-06-17.

CVE-2026-42608

CVE-2026-42608 is a critical-severity vulnerability in Getgrav Grav with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v4: 8.8
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29066
Weakness: CWE-22
Affected product: Getgrav Grav
Published: 2026-05-11
Last modified: 2026-06-17

Description

Grav is a file-based Web platform. Prior to 2.0.0-beta.2, there is a Path Traversal vulnerability within the FormFlash core component. By manipulating the session_id (passed as __form-flash-id in POST requests), an unauthenticated attacker can traverse the filesystem to create arbitrary directories and write an index.yaml file containing attacker-controlled data. This vulnerability can lead to unauthorized modification of application behavior, potential data integrity issues, and service disruption in production environments. This vulnerability is fixed in 2.0.0-beta.2.

Frequently asked questions

What is CVE-2026-42608?: Grav is a file-based Web platform. Prior to 2.0.0-beta.2, there is a Path Traversal vulnerability within the FormFlash core component. By manipulating the session_id (passed as __form-flash-id in POST requests), an unauthenticated attacker can traverse the filesystem to create arbitrary directories and write an index.yaml file containing attacker-controlled data. This vulnerability can lead to unauthorized modification of application behavior, potential data integrity issues, and service disruption in production environments. This vulnerability is fixed in 2.0.0-beta.2.
How severe is CVE-2026-42608?: CVE-2026-42608 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-42608 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42608?: CVE-2026-42608 primarily affects Getgrav Grav. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-42608?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-42608 have an EU (EUVD) identifier?: Yes. CVE-2026-42608 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29066.
When was CVE-2026-42608 published?: CVE-2026-42608 was published on 2026-05-11 and last updated on 2026-06-17.

References

https://github.com/getgrav/grav/security/advisories/GHSA-hmcx-ch82-3fv2

Affected products (2)

cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
cpe:2.3:a:getgrav:grav:2.0.0:beta1:*:*:*:*:*:*

More vulnerabilities in Getgrav Grav

CVE-2023-34251 — Critical (CVSS 9.9): Grav is a flat-file content management system. Versions prior to 1.7.42 are vulnerable to server side template…
CVE-2021-47812 — Critical (CVSS 9.8): GravCMS 1.10.7 contains an unauthenticated vulnerability that allows remote attackers to write arbitrary YAML…
CVE-2025-46199 — Critical (CVSS 9.8): Cross Site Scripting vulnerability in grav v.1.7.48 and before allows an attacker to execute arbitrary code via a…
CVE-2025-66301 — Critical (CVSS 9.6): Grav is a file-based Web platform. Prior to 1.8.0-beta.27, due to improper authorization checks when modifying critical…
CVE-2025-66844 — Critical (CVSS 9.1): In grav <1.7.49.5, a SSRF (Server-Side Request Forgery) vector may be triggered via Twig templates when page content is…
CVE-2026-42611 — High (CVSS 8.9): Grav is a file-based Web platform. Prior to 2.0.0-beta.2, a low-privileged (with the ability to create a page) user can…

All CVEs affecting Getgrav Grav →

Other CWE-22 (Path Traversal) vulnerabilities

CVE-2026-76606 — Critical (CVSS 10.0): Joomla Extension - fabrikar.com - Path Traversal via image element in Fabrik < 4.7.3 - ???.
CVE-2026-18051 — Critical (CVSS 10.0): The W3 Total Cache WordPress plugin before 2.10.5 does not properly validate the request path it uses to build cache…
CVE-2026-74764 — Critical (CVSS 10.0): Pandora contains a path traversal vulnerability in its TAR archive extraction functionality. When processing a…
CVE-2026-16940 — Critical (CVSS 10.0): The Custom Fields WordPress plugin before 1.5.1 does not validate a user-supplied file path before deletion, allowing…
CVE-2026-67429 — Critical (CVSS 10.0): Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.6, image.download and related…
CVE-2026-59555 — Critical (CVSS 10.0): Unauthenticated Arbitrary File Deletion in Participants Database <= 2.7.8.3 versions.

Browse all CWE-22 (Path Traversal) vulnerabilities →