CVE-2023-28961

Junos OS: ACX Series: IPv6 firewall filter is not installed in PFE when "from next-header ah" is used

MEDIUM
5.3
CVSS Score
Published: April 17, 2023 at 12:00 AM UTC
Updated: June 17, 2026 at 05:49 AM UTC
20 products affected across 2 vendorsJunosAcx5448Acx710

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

An Improper Handling of Unexpected Data Type vulnerability in IPv6 firewall filter processing of Juniper Networks Junos OS on the ACX Series devices will prevent a firewall filter with the term 'from next-header ah' from being properly installed in the packet forwarding engine (PFE). There is no immediate indication of an incomplete firewall filter commit shown at the CLI, which could allow an attacker to send valid packets to or through the device that were explicitly intended to be dropped. An indication that the filter was not installed can be identified with the following logs: fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_rule_prepare : Config failed: Unsupported Ip-protocol 51 in the filter lo0.0-inet6-i fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_rule_prepare : Please detach the filter, remove unsupported match and re-attach fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_process_rule : Status:104 dnx_dfw_rule_prepare failed fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_process_filter : Status:104 dnx_dfw_process_rule failed fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_update_filter_in_hw : Status:104 Could not process filter(lo0.0-inet6-i) for rule expansion Unsupported match, action present. fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_create_hw_instance : Status:104 Could not program dfw(lo0.0-inet6-i) type(IFP_DFLT_INET6_Lo0_FILTER)! [104] fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_bind_shim : [104] Could not create dfw(lo0.0-inet6-i) type(IFP_DFLT_INET6_Lo0_FILTER) fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_update_resolve : [100] Failed to bind filter(3) to bind point fpc0 ACX_DFW_CFG_FAILED: ACX Error (dfw):dnx_dfw_change_end : dnx_dfw_update_resolve (resolve type) failed This issue affects Juniper Networks Junos OS on ACX Series: All versions prior to 20.2R3-S7; 20.4 versions prior to 20.4R3-S4; 21.1 versions prior to 21.1R3-S3; 21.2 versions prior to 21.2R3-S4; 21.3 versions prior to 21.3R3; 21.4 versions prior to 21.4R3; 22.1 versions prior to 22.1R2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Affected range stops below 20.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.2R3-S7, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.4R3-S4, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.1R3-S3, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.2R3-S4, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.3R3, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.4R3, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.1R2, so it looks safe — our inference, not a vendor statement
juniper-acx1000 (environment) · juniper-acx1100 (environment) · juniper-acx2000 (environment) · juniper-acx2100 (environment) · juniper-acx2200 (environment) · juniper-acx4000 (environment) · juniper-acx500 (environment) · juniper-acx5000 (environment) · juniper-acx5048 (environment) · juniper-acx5096 (environment) · juniper-acx5400 (environment) · juniper-acx5448 (environment) · juniper-acx5800 (environment) · juniper-acx6300 (environment) · juniper-acx6360 (environment) · juniper-acx710 (environment) · juniper-acx7100-32c (environment) · juniper-acx7100-48l (environment) · juniper-acx7509 (environment)
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-241NVD-CWE-Other

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