CVE-2026-107891
musl libc Integer Overflow in Regular Expression Compilation
Description
musl libc before 1.2.7, when an untrusted regular expression is used with regcomp, has multiple integer overflows, possibly leading to incorrect allocation sizes and out-of-bounds heap writes.
INFO
Published Date :
Nov. 5, 2026, 4:17 p.m.
Last Modified :
Nov. 5, 2026, 5:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-107891
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update musl libc to version 1.2.7 or later.
- Avoid using untrusted regular expressions with regcomp.
- Review and validate regular expression inputs.
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-2026-107891.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-107891 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-2026-107891
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).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-107891 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-107891 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.
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CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 05, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/10/21/18 -
New CVE Received by [email protected]
Nov. 05, 2026
Action Type Old Value New Value Added Description musl libc before 1.2.7, when an untrusted regular expression is used with regcomp, has multiple integer overflows, possibly leading to incorrect allocation sizes and out-of-bounds heap writes. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-190 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/107xxx/CVE-2026-107891.json">CVE-2026-107891</a> Added Reference https://git.musl-libc.org/cgit/musl/commit/?id=7813e9119eb5fe681b6750b8a033a0490bca0941 Added Reference https://musl.libc.org Added Reference https://www.openwall.com/lists/musl/2026/10/21/1