CVE-2026-8376
Perl versions through 5.43.10 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds
Description
Perl versions through 5.43.10 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds. Perl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer. A caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time.
INFO
Published Date :
May 26, 2026, 12:16 a.m.
Last Modified :
May 27, 2026, 7:16 p.m.
Remotely Exploit :
Yes !
Source :
9b29abf9-4ab0-4765-b253-1875cd9b441e
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | HIGH | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update Perl to a version later than 5.43.10.
- Ensure builds are not 32-bit if using vulnerable versions.
- Avoid compiling untrusted regular expressions.
- Recompile affected Perl modules.
Public PoC/Exploit Available at Github
CVE-2026-8376 has a 8 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-8376.
| URL | Resource |
|---|---|
| https://github.com/Perl/perl5/commit/5e7f119eb2bb1181be908701f22bf7068e722f1c.patch | Patch |
| http://www.openwall.com/lists/oss-security/2026/05/26/1 | Mailing List Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-8376 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-8376
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
Dockerfile Python
None
Dockerfile Python
This was created for workshop 1 of PlatformCon - https://platformcon.com/sessions/hunting-compromised-software-dependencies-inside-kubernetes-workloads
Dockerfile
A hardened, automated DevSecOps pipeline — containerized app with CI/CD, security scanning, and monitoring deployed on a self-hosted Linux server.
Dockerfile Python
None
Python Dockerfile
Lightweight, statically compiled Go binaries for distroless OCI images: packaged as apk via melange.
Go
Infrastructure as Code for a self-hosted WordPress stack: Terraform, Ansible, Docker with distroless OCI images built via apko/melange with automated CVE scanning.
HCL Shell Jinja Go PHP Dockerfile HTML Python
Contour art generator with a web UI. Tweak noise, colors and line styles, then export at any resolution.
Python HTML CSS Dockerfile Shell JavaScript
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-8376 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-8376 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L -
Initial Analysis by [email protected]
May. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:* versions up to (including) 5.43.10 Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2026/05/26/1 Types: Mailing List, Third Party Advisory Added Reference Type CPANSec: https://github.com/Perl/perl5/commit/5e7f119eb2bb1181be908701f22bf7068e722f1c.patch Types: Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
May. 26, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/05/26/1 -
New CVE Received by 9b29abf9-4ab0-4765-b253-1875cd9b441e
May. 26, 2026
Action Type Old Value New Value Added Description Perl versions through 5.43.10 have a heap buffer overflow when compiling regular expressions with a repeated fixed string on 32-bit builds. Perl_study_chunk in regcomp_study.c checked the size of the joined substring buffer in characters rather than bytes. For a quantified fixed substring with a large minimum count, the byte length mincount * l could overflow SSize_t, producing an undersized SvGROW allocation; the subsequent copy writes past the end of the buffer. A caller that compiles an attacker-controlled regular expression on a 32-bit perl build triggers a heap buffer overflow at compile time. Added CWE CWE-680 Added Reference https://github.com/Perl/perl5/commit/5e7f119eb2bb1181be908701f22bf7068e722f1c.patch