CVE-2026-44318
free5GC: BSF concurrent PUT /nbsf-management/v1/subscriptions/{subId} crashes the BSF process via concurrent map read/write on Subscriptions
Description
free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's BSF PUT /nbsf-management/v1/subscriptions/{subId} handler has an unsynchronized write on the global Subscriptions map. The handler first reads the map under RLock() via BSFContext.GetSubscription(subId), but if the subscription does not exist, ReplaceIndividualSubcription() writes back to the same map directly without taking the mutex (bsfContext.BsfSelf.Subscriptions[subId] = subscription). Under concurrent authenticated PUT load, one goroutine can read while another writes the map, which causes the Go runtime to abort the process with fatal error: concurrent map read and map write (Go runtime panics that come from concurrent map access bypass recover() and terminate the process). The BSF container exits with code 2 -- the entire BSF SBI surface goes down until restart. This vulnerability is fixed in 4.2.2.
INFO
Published Date :
May 27, 2026, 5:16 p.m.
Last Modified :
Oct. 14, 2026, 8:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update free5GC to version 4.2.2 or later.
- Apply the fix for unsynchronized map writes.
- Restart the BSF container after updating.
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-2026-44318.
| URL | Resource |
|---|---|
| https://github.com/free5gc/bsf/commit/277908565fd628d974a13ef562b81a8b7b519ffa | Patch |
| https://github.com/free5gc/bsf/pull/7 | Issue Tracking Patch |
| https://github.com/free5gc/free5gc/issues/926 | Exploit Issue Tracking |
| https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7 | Exploit Vendor Advisory |
| https://github.com/free5gc/free5gc/issues/926 | Exploit Issue Tracking |
| https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7 | Exploit Vendor 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-2026-44318 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-2026-44318
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-2026-44318 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-44318 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 Translated by [email protected]
Oct. 14, 2026
Action Type Old Value New Value Added Translation Title: free5gc, Description: free5GC es una implementación de código abierto de la red central 5G. Antes de la versión 4.2.2, el gestor BSF PUT /nbsf-management/v1/subscriptions/{subId} de free5GC tiene una escritura no sincronizada en el mapa global de Subscriptions. El gestor primero lee el mapa bajo RLock() a través de BSFContext.GetSubscription(subId), pero si la suscripción no existe, ReplaceIndividualSubcription() escribe de nuevo en el mismo mapa directamente sin tomar el mutex (bsfContext.BsfSelf.Subscriptions[subId] = subscription). Bajo una carga PUT autenticada concurrente, una goroutine puede leer mientras otra escribe en el mapa, lo que hace que el tiempo de ejecución de Go aborte el proceso con un error fatal: lectura y escritura concurrente de mapa (los panics del tiempo de ejecución de Go que provienen del acceso concurrente al mapa evitan recover() y terminan el proceso). El contenedor BSF sale con código 2 -- toda la superficie SBI del BSF se cae hasta el reinicio. Esta vulnerabilidad se corrige en la versión 4.2.2. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'free5gc', 'product': 'free5gc', 'versions': [{'status': 'affected', 'version': '< 4.2.2'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-44318', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-05-27T17:34:59.963720Z'} -
Initial Analysis by [email protected]
May. 28, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:* versions up to (excluding) 4.2.2 Added Reference Type GitHub, Inc.: https://github.com/free5gc/bsf/commit/277908565fd628d974a13ef562b81a8b7b519ffa Types: Patch Added Reference Type GitHub, Inc.: https://github.com/free5gc/bsf/pull/7 Types: Issue Tracking, Patch Added Reference Type CISA-ADP: https://github.com/free5gc/free5gc/issues/926 Types: Exploit, Issue Tracking Added Reference Type GitHub, Inc.: https://github.com/free5gc/free5gc/issues/926 Types: Exploit, Issue Tracking Added Reference Type CISA-ADP: https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7 Types: Exploit, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7 Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 27, 2026
Action Type Old Value New Value Added Reference https://github.com/free5gc/free5gc/issues/926 Added Reference https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7 -
New CVE Received by [email protected]
May. 27, 2026
Action Type Old Value New Value Added Description free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's BSF PUT /nbsf-management/v1/subscriptions/{subId} handler has an unsynchronized write on the global Subscriptions map. The handler first reads the map under RLock() via BSFContext.GetSubscription(subId), but if the subscription does not exist, ReplaceIndividualSubcription() writes back to the same map directly without taking the mutex (bsfContext.BsfSelf.Subscriptions[subId] = subscription). Under concurrent authenticated PUT load, one goroutine can read while another writes the map, which causes the Go runtime to abort the process with fatal error: concurrent map read and map write (Go runtime panics that come from concurrent map access bypass recover() and terminate the process). The BSF container exits with code 2 -- the entire BSF SBI surface goes down until restart. This vulnerability is fixed in 4.2.2. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-362 Added CWE CWE-820 Added Reference https://github.com/free5gc/bsf/commit/277908565fd628d974a13ef562b81a8b7b519ffa Added Reference https://github.com/free5gc/bsf/pull/7 Added Reference https://github.com/free5gc/free5gc/issues/926 Added Reference https://github.com/free5gc/free5gc/security/advisories/GHSA-27ph-8q4f-h7m7