CVE-2026-41135 json
free5GC PCF: Memory Leak via CORS Middleware Registration in HTTP Handler Leads to Denial of Service
published 2026-04-21 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-24575 , GHSA-98cp-84m9-q3qp , GO-2026-5278
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
free5GC UDR is the Policy Control Function (PCF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. A memory leak vulnerability in versions prior to 1.4.3 allows any unauthenticated attacker with network access to the PCF SBI interface to cause uncontrolled memory growth by sending repeated HTTP requests to the OAM endpoint. The root cause is a `router.Use()` call inside an HTTP handler that registers a new CORS middleware on every incoming request, permanently growing the Gin router's handler chain. This leads to progressive memory exhaustion and eventual Denial of Service of the PCF, preventing all UEs from obtaining AM and SM policies and blocking 5G session establishment. Version 1.4.3 contains a patch.
Patch / fix
- go github.com/free5gc/pcf 1.4.3
- free5gc pcf 1.4.3
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/free5gc/free5gc/security/advisories/GHSA-98cp-84m9-q3qp referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/free5gc/pcf | <1.4.3 |
1.4.3 |
Affected products
- free5gc pcf
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/free5gc/pcf/commit/599803b1b2eb4611e26d5216481ee142bce71a16
patch
-
github.com
/free5gc/free5gc/security/advisories/GHSA-98cp-84m9-q3qp
exploit, web, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-41135
advisory
-
github.com
/free5gc/free5gc
package
Sources
- CVE List CVE-2026-41135
- GitHub Advisory GHSA-98cp-84m9-q3qp
- NVD CVE-2026-41135
- OSV GO-2026-5278
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.