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CVE Record

CVE-2025-15686: Open5GS HSS Service fd_msg_sess_get denial of service

A vulnerability has been found in Open5GS up to 2.7.6. Affected by this issue is the function fd_msg_sess_get of the component HSS Service. Such manipulation of the argument Session-Id leads to denial of service. The attack may be performed from remote. The exploit has been disclosed to the public and may be used. The project locked and limited conversation to collaborators.

MediumCVSS 5.3Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

Open5GS versions 2.7.0 through 2.7.6 contain a remotely triggerable HSS service flaw that can cause denial of service. Successful abuse could interrupt mobile-core authentication or subscriber-related operations. The supplied evidence indicates public exploit material, but not confirmed attacks in operational environments.

Executive priority

Treat this as a prompt availability-risk review, especially where Open5GS supports production mobile-core services without redundancy. Prioritize inventory, access restriction, monitoring, and vendor guidance. Escalate if affected HSS instances are broadly reachable or repeated service failures are observed.

Technical view

Manipulating the Session-Id argument handled by fd_msg_sess_get in the Open5GS HSS service can cause a denial of service. The issue is classified as CWE-404 and scored CVSS 4.0 at 5.3. Network access and low privileges are required; no user interaction is needed, and the stated impact is limited to availability.

Likely exposure

Exposure is most likely in Open5GS deployments running versions 2.7.0–2.7.6 where an untrusted or compromised low-privilege network participant can reach the HSS service. Internet exposure is not established by the supplied sources. Operational significance depends on HSS redundancy and recovery behavior.

Exploitation context

A proof-of-concept packet capture has been publicly disclosed, and the CVSS assessment marks exploit maturity as proof-of-concept. CVE-2025-15686 is not listed as known exploited in the supplied KEV signal. Public disclosure increases testing and abuse potential, but active exploitation is unconfirmed.

Researcher notes

The supplied record identifies fd_msg_sess_get and Session-Id manipulation but does not establish the precise failure mechanism, persistence, recovery requirements, or an official fixed version. The GitHub discussion was reportedly restricted. Avoid inferring memory corruption, confidentiality impact, or active campaigns from the available evidence.

Mitigation direction

  • Inventory Open5GS deployments and identify versions 2.7.0 through 2.7.6.
  • Check Open5GS vendor guidance for a corrected release or official mitigation.
  • Restrict HSS service access to trusted network peers using existing segmentation controls.
  • Monitor HSS availability and anomalous Session-Id-related failures.
  • Use operational redundancy and tested recovery procedures to limit service disruption.

Validation and detection

  • Confirm the deployed Open5GS version from trusted configuration or package records.
  • Map which systems and network identities can reach the HSS service.
  • Review HSS logs and monitoring for crashes, restarts, or Session-Id processing errors.
  • Verify segmentation prevents unauthorized or unnecessary peers from accessing HSS.
  • Confirm vendor guidance and document whether the deployment remains affected.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-404: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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cve · low confidence lookup

CVE-2025-15686 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
5.3 (4.0)
Known Exploited
No
Published

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

4CVSS vectors
6Timeline events
1ADP providers
8Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: pocAutomatable: noTechnical Impact: partial

CVSS vector scores

4 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
5.3CVSS 4.0MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P——VulDB
4.3CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R2.81.4VulDB
4.3CVSS 3.0MediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R2.81.4VulDB
4CVSS 2.0MediumAV:N/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:ND/RC:UR82.9VulDB

Vulnerability scoring details

Base CVSS 4.0 score

5.3Medium
CVSS 4.0 vector shape for CVE-2025-15686Attack VectorAttack ComplexityAttack RequirementsPrivileges RequiredUser InteractionVS ConfidentialityVS IntegrityVS AvailabilitySS ConfidentialitySS IntegritySS Availability

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Attack Requirements
NonePresent
Privileges Required
NoneLowHigh
User Interaction
NonePassiveActive
VS Confidentiality
HighLowNone
VS Integrity
HighLowNone
VS Availability
HighLowNone
SS Confidentiality
HighLowNone
SS Integrity
HighLowNone
SS Availability
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timelineVulDB

    Advisory disclosed

  2. Source timelineVulDB

    VulDB entry created

  3. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  4. Source timelineVulDB

    VulDB entry last update

  5. CVE publishedCVE Program

    The CVE record was published.

  6. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/aOpen5GS2.7.0, 2.7.1, 2.7.2, 2.7.3, 2.7.4, 2.7.5, 2.7.6Listed
Weakness

CWE details

CWE-404

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-404 · source CWE mapping

Improper Resource Shutdown or Release

Improper Resource Shutdown or Release represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs