dbcve.org
Openairinterface5gApplication · Openairinterface

CVE-2026-37232

HIGH · 8.6 CVSS v3.1 Published 2026-06-01
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An issue was discovered in OpenAirInterface5G 2.4.0 (nr-softmodem) in the E2SM-KPM RAN Function's PRB utilization metric calculation. The functions fill_RRU_PrbTotDl() and fill_RRU_PrbTotUl() in openair2/E2AP/RAN_FUNCTION/O-RAN/ran_func_kpm_subs.c (lines 182 and 197) compute PRB usage percentages by dividing by the difference of two consecutive total_prb_aggregate samples without checking for zero. When a malicious xApp sends a high volume of E42_RIC_SUBSCRIPTION_REQUESTs via the FlexRIC iApp (port 36422/SCTP), the E2 Agent generates KPM Indication reports at high frequency. If two consecutive sampling intervals yield identical PRB aggregate values, the divisor becomes zero, triggering SIGFPE and crashing the entire 5G base station process (nr-softmodem). This results in complete 5G cell service interruption for all connected UEs. No authentication is required.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

OpenAirInterface5G 2.4.0 nr-softmodem contains a division by zero vulnerability in the E2SM-KPM RAN Function's PRB utilization calculation. Functions fill_RRU_PrbTotDl() and fill_RRU_PrbTotUl() compute PRB percentages by dividing by the difference of consecutive total_prb_aggregate samples without validating the divisor is non-zero. An unauthenticated malicious xApp sending rapid E42_RIC_SUBSCRIPTION_REQUESTs can trigger identical consecutive PRB samples, causing SIGFPE and crashing the entire 5G base station process.

MitigationAdd input validation to ensure the PRB sample difference (divisor) is non-zero before performing division in both fill_RRU_PrbTotDl() and fill_RRU_PrbTotUl(); additionally implement rate limiting on E2AP subscription requests to mitigate high-frequency sample generation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Openairinterface5gApplication
Affected:= 2.4.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify OpenAirInterface5G version
    Run 'git log' or check version metadata in the OpenAirInterface5G installation directory to confirm the installed version is 2.4.0
    Affected if Version is exactly 2.4.0
  2. Confirm E2SM-KPM module is enabled
    Inspect the E2SM-KPM configuration files or runtime settings for the nr-softmodem to determine if the E2SM-KPM RAN Function is loaded and active
    Affected if E2SM-KPM RAN Function is enabled and processing PRB metrics
  3. Verify nr-softmodem process is running
    Run 'ps aux | grep nr-softmodem' or check process list to confirm the nr-softmodem process is active
    Affected if nr-softmodem process is running with E2SM-KPM support
  4. Check for presence of vulnerable functions
    Search the source code for fill_RRU_PrbTotDl() and fill_RRU_PrbTotUl() functions in the E2SM-KPM implementation files
    Affected if These functions exist without zero-check validation on the divisor
  5. Monitor for SIGFPE crashes
    Check system logs or dmesg for SIGFPE signals affecting nr-softmodem, or monitor for unexpected nr-softmodem restarts
    Affected if SIGFPE crashes of nr-softmodem are occurring

Running OpenAirInterface5G version 2.4.0 with the E2SM-KPM RAN Function enabled allows a malicious xApp to trigger a division by zero and crash nr-softmodem.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Add input validation to ensure the PRB sample difference (divisor) is non-zero before performing division in both fill_RRU_PrbTotDl() and fill_RRU_PrbTotUl(); additionally implement rate limiting on E2AP subscription requests to mitigate high-frequency sample generation.

Fix this in Openairinterface5g Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing8.0 h
  • Review / QA4.0 h
24.0 hours of engineering $4,160
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,656.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-37232 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-37232 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data