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Fencer Intel
high 7.5

CVE-2026-124437 json

Scriban before 7.5.3 Denial of Service via Unguarded Builtins and Recursion

published 19d ago modified 3d ago also EUVD-2026-119563 , GHSA-95w2-9mjq-6c74

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository scriban/scriban. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 36%
public exploits
0
none known

Summary

Scriban before 7.5.3 contains a resource exhaustion vulnerability that allows untrusted template authors to exhaust memory and CPU because builtins like math.format, regex.replace and string.escape skip the LimitToString allocation guard. Attackers can submit small templates using huge format precision specifiers, shared-structure array comparison, BigInteger multiplication or exponential function recursion that ignore LoopLimit and CancellationToken, crashing or stalling multi-tenant hosts.

Patch / fix

  • scriban scriban 7.5.3

Is CVE-2026-124437 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 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
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 4.0 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/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
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • scriban scriban

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of scriban/scriban published their own advisory on GitHub. Reviewed sources take precedence over it.