Resource exhaustion in Scriban
CVE-2026-74788
Scriban before 7.0.0 (affected versions <= 6.6.0) contains an uncontrolled memory allocation vulnerability in the string.pad_left and string.pad_right template functions, which perform no validation on the width parameter before delegating to .NET's String.PadLeft/PadRight. When an application exposes Scriban to untrusted template input, an attacker can supply an arbitrarily large width value (e.g., 500,000,000) to trigger ~1GB memory allocations in a single call, resulting in OutOfMemoryException and denial of service. The TemplateContext.LimitToString limit does not prevent this because it is only enforced after the string has been fully allocated.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (39.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Scriban — versions 0, 7.0.0
Weakness classification (CWE)
References
- github.com/scriban/scriban/security/advisories/GHSA-v66j-x4hw-fv9g (vendor-advisory)
- www.vulncheck.com/advisories/scriban-before-denial-of-service-via-string-pad-le… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-74788?
- CVE-2026-74788 is a high-severity vulnerability in Scriban, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-08-16.
- How severe is CVE-2026-74788?
- High severity. CVSS v3 base score is 7.5 out of 10.