skvadrik re2c up to 4.4 src/parse/ast.cc check_and_merge_special_rules null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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3.1$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in skvadrik re2c up to 4.4. The affected element is the function check_and_merge_special_rules of the file src/parse/ast.cc. Such manipulation leads to null pointer dereference. This vulnerability is referenced as CVE-2026-2903. The attack can only be performed from a local environment. Furthermore, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in skvadrik re2c up to 4.4. It has been rated as problematic. Affected by this issue is the function check_and_merge_special_rules of the file src/parse/ast.cc. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-2903. The exploitation is known to be easy. Local access is required to approach this attack. Technical details as well as a public exploit are known.

The exploit is available at github.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 299747 (Linux Distros Unpatched Vulnerability : CVE-2026-2903), which helps to determine the existence of the flaw in a target environment.

Applying the patch febeb977936f9519a25d9fbd10ff8256358cdb97 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (299747). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 3.3
VulDB Meta Temp Score: 3.1

VulDB Base Score: 3.3
VulDB Temp Score: 3.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 3.3
CNA Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 299747
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-2903

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: febeb977936f9519a25d9fbd10ff8256358cdb97

Timelineinfo

02/20/2026 Advisory disclosed
02/20/2026 +0 days VulDB entry created
02/23/2026 +3 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 571
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-2903 (🔒)
GCVE (CVE): GCVE-0-2026-2903
GCVE (VulDB): GCVE-100-347210
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 02/20/2026 21:07
Updated: 02/23/2026 03:22
Changes: 02/20/2026 21:07 (60), 02/23/2026 00:53 (2), 02/23/2026 03:22 (30)
Complete: 🔍
Submitter: Oneafter
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #755030: skvadrik re2c 04f1424 NULL Pointer Dereference (by Oneafter)

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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