CVE-2026-1736Public exploitNetwork attack vector

Remote SGW-C crash via invalid session type

Published Feb 2, 2026 · Updated Feb 2, 2026

Reachable assertion in Open5GS SGW-C 2.7.0 through 2.7.6 allows remote attackers to crash the process via crafted GTPv2-C messages. The S11 handler retains an invalid session_type derived from a malformed PAA in a Create Session Response, then passes that value to a fatal assertion while processing a follow-up tunnel request. An attacker must act as or inject traffic from a PGW and MME on the GTP control plane; successful exploitation aborts SGW-C and interrupts EPC service.

CVSS severity5.3
Medium
EPSS probability0.63%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in Open5GS SGW-C 2.7.0 through 2.7.6 allows remote attackers to crash the process via crafted GTPv2-C messages. The S11 handler retains an invalid session_type derived from a malformed PAA in a Create Session Response, then passes that value to a fatal assertion while processing a follow-up tunnel request. An attacker must act as or inject traffic from a PGW and MME on the GTP control plane; successful exploitation aborts SGW-C and interrupts EPC service.

The record

CVE
CVE-2026-1736
Published
Feb 2, 2026
Updated
Feb 2, 2026
Vendor
Open5GS
Product
Open5GS
Classifications
CWE-617, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.7.0
  2. Affected versionversion=2.7.1
  3. Affected versionversion=2.7.2
  4. Affected versionversion=2.7.3
  5. Affected versionversion=2.7.4
  6. Affected versionversion=2.7.5
  7. Affected versionversion=2.7.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Open5GS · Open5GSversion=2.7.0; version=2.7.1; version=2.7.2; version=2.7.3; version=2.7.4; version=2.7.5; version=2.7.6

Published CVSS scores

5.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
5.0VulDBAV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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