Junos OS: Improper Handling of Length Parameter Inconsistency
CVE-2023-28964 is a high-severity improper handling of length parameter inconsistency vulnerability in Junos OS from Juniper Networks, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 18.1R3-S11, 18.2R3-S6, 18.3R3-S4 as the first without the flaw, so updating Junos OS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.65% chance of exploitation within 30 days, higher than 52% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Junos OS to 18.1R3-S11 or 18.2R3-S6 or 18.3R3-S4 or 18.4R3-S6, whichever matches your release line, or a later version.
- Update Junos OS Evolved to 20.1R3-EVO or 20.2R2-EVO or 20.3R2-EVO, whichever matches your release line, or a later version.
- Update Junos to 18.1 or a later version.
- Read the advisory on supportportal.juniper.net for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Juniper Networks | Junos OS | before 18.1R3-S11; 18.2 up to, but not including, 18.2R3-S6; 18.3 up to, but not including, 18.3R3-S4; 18.4 up to, but not including, 18.4R3-S6; 19.1 up to, but not including, 19.1R3-S4; 19.2 up to, but not including, 19.2R3-S1; 19.3 up to, but not including, 19.3R3-S1; 19.4 up to, but not including, 19.4R3; and 3 more ranges | 18.1R3-S11, 18.2R3-S6, 18.3R3-S4, 18.4R3-S6, 19.1R3-S4, 19.2R3-S1 |
| Juniper Networks | Junos OS Evolved | before 20.1R3-EVO; 20.2 up to, but not including, 20.2R2-EVO; 20.3 up to, but not including, 20.3R2-EVO | 20.1R3-EVO, 20.2R2-EVO, 20.3R2-EVO |
| Juniper Networks | Junos | before 18.1; 18.1; 18.2; 18.3; 18.4; 19.1; 19.2; 19.3; and 4 more ranges | 18.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (juniper.net).
Official description
An Improper Handling of Length Parameter Inconsistency vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a network based, unauthenticated attacker to cause an RPD crash leading to a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. Upon receipt of a malformed BGP flowspec update, RPD will crash resulting in a Denial of Service. This issue affects Juniper Networks Junos OS: All versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R3-S6; 19.1 versions prior to 19.1R3-S4; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2; 20.3 versions prior to 20.3R1-S1, 20.3R2; Juniper Networks Junos OS Evolved: All versions prior to 20.1R3-EVO; 20.2 versions prior to 20.2R2-EVO; 20.3 versions prior to 20.3R2-EVO;
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Handling of Length Parameter Inconsistency
The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.
How developers prevent this class of flaw
- When processing structured incoming data containing a size field followed by raw data, ensure that you identify and resolve any inconsistencies between the size field and the actual size of the data.
- Do not let the user control the size of the buffer.
- Validate that the length of the user-supplied data is consistent with the buffer size.
More Improper Handling of Length Parameter Inconsistency vulnerabilities (CWE-130)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in Junos OS
- 7.5 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
Recent Improper Handling of Length Parameter Inconsistency vulnerabilities
- 7.5 High severity
- 8.6 High severity
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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