4.8
MEDIUM CVSS 4.0
CVE-2026-2240
janet-lang janet compile.c janetc_pop_funcdef out-of-bounds
Description

A vulnerability has been found in janet-lang janet up to 1.40.1. The impacted element is the function janetc_pop_funcdef of the file src/core/compile.c. Such manipulation leads to out-of-bounds read. The attack must be carried out locally. The exploit has been disclosed to the public and may be used. The name of the patch is 4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5. A patch should be applied to remediate this issue.

INFO

Published Date :

Feb. 9, 2026, 4:16 p.m.

Last Modified :

Feb. 9, 2026, 4:16 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-2240 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
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 LOW [email protected]
CVSS 3.1 LOW [email protected]
CVSS 4.0 MEDIUM [email protected]
Solution
Apply the provided patch to the janet-lang source code to fix the out-of-bounds read vulnerability.
  • Apply the patch `4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5` to janet-lang source.
  • Recompile janet-lang after applying the patch.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-2240 is associated with the following CWEs:

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-2026-2240 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-2240 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.

  • New CVE Received by [email protected]

    Feb. 09, 2026

    Action Type Old Value New Value
    Added Description A vulnerability has been found in janet-lang janet up to 1.40.1. The impacted element is the function janetc_pop_funcdef of the file src/core/compile.c. Such manipulation leads to out-of-bounds read. The attack must be carried out locally. The exploit has been disclosed to the public and may be used. The name of the patch is 4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5. A patch should be applied to remediate this issue.
    Added CVSS V4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/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
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
    Added CVSS V2 (AV:L/AC:L/Au:S/C:N/I:N/A:P)
    Added CWE CWE-119
    Added CWE CWE-125
    Added Reference https://github.com/janet-lang/janet/
    Added Reference https://github.com/janet-lang/janet/commit/4dd08a4cdef5b1c42d9a2c19fc24412e97ef51d5
    Added Reference https://github.com/janet-lang/janet/issues/1702
    Added Reference https://github.com/janet-lang/janet/issues/1702#issuecomment-3790473369
    Added Reference https://github.com/oneafter/0123/blob/main/ja4/repro
    Added Reference https://vuldb.com/?ctiid.344979
    Added Reference https://vuldb.com/?id.344979
    Added Reference https://vuldb.com/?submit.753155
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 4.8
Attack Vector
Attack Complexity
Attack Requirements
Privileges Required
User Interaction
VS Confidentiality
VS Integrity
VS Availability
SS Confidentiality
SS Integrity
SS Availability
Base CVSS Score: 3.3
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 1.7
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact