CVE-2023-34253
CVE-2023-34253 is a high-severity vulnerability in Getgrav Grav with a CVSS 3.x base score of 8.8. 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-94.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 2% (79th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-94
- Affected product: Getgrav Grav
- Published:
- Last modified:
Description
Grav is a flat-file content management system. Prior to version 1.7.42, the denylist introduced in commit 9d6a2d to prevent dangerous functions from being executed via injection of malicious templates was insufficient and could be easily subverted in multiple ways -- (1) using unsafe functions that are not banned, (2) using capitalised callable names, and (3) using fully-qualified names for referencing callables. Consequently, a low privileged attacker with login access to Grav Admin panel and page creation/update permissions is able to inject malicious templates to obtain remote code execution. A patch in version 1.7.42 improves the denylist.
Frequently asked questions
- What is CVE-2023-34253?
- Grav is a flat-file content management system. Prior to version 1.7.42, the denylist introduced in commit 9d6a2d to prevent dangerous functions from being executed via injection of malicious templates was insufficient and could be easily subverted in multiple ways -- (1) using unsafe functions that are not banned, (2) using capitalised callable names, and (3) using fully-qualified names for referencing callables. Consequently, a low privileged attacker with login access to Grav Admin panel and page creation/update permissions is able to inject malicious templates to obtain remote code execution. A patch in version 1.7.42 improves the denylist.
- How severe is CVE-2023-34253?
- CVE-2023-34253 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2023-34253 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-34253?
- CVE-2023-34253 affects Getgrav Grav. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2023-34253?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-34253 published?
- CVE-2023-34253 was published on 2023-06-14 and last updated on 2026-06-17.
References
- https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1952-L2190
- https://github.com/getgrav/grav/commit/71bbed12f950de8335006d7f91112263d8504f1b
- https://github.com/getgrav/grav/security/advisories/GHSA-j3v8-v77f-fvgm
- https://huntr.dev/bounties/3ef640e6-9e25-4ecb-8ec1-64311d63fe66/
- https://www.github.com/getgrav/grav/commit/9d6a2dba09fd4e56f5cdfb9a399caea355bfeb83
Affected products (1)
- cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
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-2026-42608 — Critical (CVSS 9.1): Grav is a file-based Web platform. Prior to 2.0.0-beta.2, there is a Path Traversal vulnerability within the FormFlash…
- 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…
All CVEs affecting Getgrav Grav →
Other CWE-94 (Code Injection) vulnerabilities
- CVE-2026-57624 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Blocksy Companion Pro <= 2.1.46 versions.
- CVE-2026-10134 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 allows an attacker to read every secret available to the Langflow process, read…
- CVE-2026-53576 — Critical (CVSS 10.0): Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, the authentication filter…
- CVE-2026-10561 — Critical (CVSS 10.0): IBM Langflow OSS 1.0.0 through 1.9.3 has an vulnerability due to an improper isolation of Python execution combined…
- CVE-2026-25470 — Critical (CVSS 10.0): Improper Control of Generation of Code ('Code Injection') vulnerability in ACPT ACPT (Pro) - Custom Post Types Plugin…
- CVE-2026-48836 — Critical (CVSS 10.0): Unauthenticated Remote Code Execution (RCE) in Easy Invoice <= 2.1.19 versions.