# CVE-2026-124439: Scriban before 7.5.3 Denial of Service via Uncatchable StackOverflowException

Status: published. Published: 2026-11-08. Updated: 2026-11-10.

Scriban and Scriban.Signed before 7.5.3 contain uncontrolled recursion flaws in which postfix member, indexer, and call chains bypass ExpressionDepthLimit, array comparison lacks depth and cycle checks, and object.eval bypasses RecursiveLimit. Attackers who can supply templates can trigger an uncatchable StackOverflowException that terminates the host process.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- scriban / scriban (Scriban): ≥ 0; < 7.5.3 (affected, semver); 7.5.3 (unaffected, semver). Source: CNA: VulnCheck
- scriban / scriban (Scriban.Signed): ≥ 0; < 7.5.3 (affected, semver); 7.5.3 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 8.7 (high); 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; source: CNA: VulnCheck

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: VulnCheck

- CVSS 4.0: 8.7 (high); 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: 0.45% as of 2026-11-10; percentile 39.68%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-674

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/scriban/scriban/security/advisories/GHSA-mvmw-9jxc-7pr2 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/scriban-before-7.5.3-denial-of-service-via-uncatchable-stackoverflowexception (CNA: VulnCheck; third-party-advisory)

- https://github.com/scriban/scriban/security/advisories/GHSA-mvmw-9jxc-7pr2 (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/scriban-before-7.5.3-denial-of-service-via-uncatchable-stackoverflowexception (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-124439; retrieved 2026-11-10; source updated 2026-11-10

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-124439; retrieved 2026-11-08; source updated 2026-11-08

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-124439; retrieved 2026-11-10; source updated Not reported

Revision: e26704b091d59b67b5418217a71c6a1b167d56f8550ca5998a420a5b67da64f6

Canonical: https://y2.dev/cve/CVE-2026-124439

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