# CVE-2026-74788: Scriban before 7.0.0 Denial of Service via string.pad_left/pad_right

> Attackers can cause denial of service in applications using Scriban by supplying large width values to pad functions, triggering excessive memory allocation.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** GHSA-3qxv-x8gq-wgff, GHSA-v66j-x4hw-fv9g

## What is CVE-2026-74788?

CVE-2026-74788 is a high-severity denial of service vulnerability in scriban, published on 16 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-74788?

4 open source packages ship an affected version, including Scriban and Scriban.Signed.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Scriban` | NuGet | All versions | 7.0.0 |
| `Scriban` | NuGet | All versions | 7.0.0 |
| `Scriban.Signed` | NuGet | All versions | 7.0.0 |
| `Scriban.Signed` | NuGet | All versions | 7.0.0 |

## How do I fix CVE-2026-74788?

Upgrade Scriban to 7.0.0 or later.

## Is CVE-2026-74788 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74788 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-74788 and fix it if it is affected.

What it is: CVE-2026-74788 is a high-severity denial of service vulnerability in scriban, published on 16 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-74788 exists.

Affected packages and fixed versions:
- Scriban (NuGet): affected all versions; fixed in 7.0.0
- Scriban (NuGet): affected all versions; fixed in 7.0.0
- Scriban.Signed (NuGet): affected all versions; fixed in 7.0.0
- Scriban.Signed (NuGet): affected all versions; fixed in 7.0.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-74788/ (Markdown: https://insights.sbomify.com/CVE-2026-74788/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-74788
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-74788
- OSV: https://osv.dev/vulnerability/CVE-2026-74788

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-74788/
Summaries are generated and may contain mistakes; the official description above is the record.