CVE-2024-20456: A vulnerability in the boot process of Cisco IOS XR Software could allow an authenticated, local attacker with high privileges to bypass the…
Noroxi assessment
Priority: Monitor (action score 26/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
- Someone with local access to the system can trigger it. Administrator privileges are required. No user action is required. No special conditions are required; it is repeatable.
- According to the record, no fixed version is available yet.
- Mentioned 2 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
A vulnerability in the boot process of Cisco IOS XR Software could allow an authenticated, local attacker with high privileges to bypass the Cisco Secure Boot functionality and load unverified software on an affected device. To exploit this successfully, the attacker must have root-system privileges on the affected device. This vulnerability is due to an error in the software build process. An attacker could exploit this vulnerability by manipulating the system’s configuration options to bypass some of the integrity checks that are performed during the booting process. A successful exploit could allow the attacker to control the boot configuration, which could enable them to bypass of the requirement to run Cisco signed images or alter the security properties of the running system.
- Published
- Jul 10, 2024
- Updated
- Jun 17, 2026
- EPSS
- 0.1% · 8th percentile
- CWE
- CWE-732
Report tools
Action score
26
Low priority for now.
- CVSS
- 26 / 40 · 6.7 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · cisco
- 6.7
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| cisco | ios xr | cpe:2.3:o:cisco:ios_xr |
| cisco | 8011-4g24y4h-i | cpe:2.3:h:cisco:8011-4g24y4h-i |
| cisco | 8101-32fh | cpe:2.3:h:cisco:8101-32fh |
| cisco | 8101-32fh-o | cpe:2.3:h:cisco:8101-32fh-o |
| cisco | 8101-32h-o | cpe:2.3:h:cisco:8101-32h-o |
| cisco | 8102-28fh-dpu-o | cpe:2.3:h:cisco:8102-28fh-dpu-o |
| cisco | 8102-64h | cpe:2.3:h:cisco:8102-64h |
| cisco | 8102-64h-o | cpe:2.3:h:cisco:8102-64h-o |
| cisco | 8111-32eh-o | cpe:2.3:h:cisco:8111-32eh-o |
| cisco | 8122-64eh-o | cpe:2.3:h:cisco:8122-64eh-o |
| cisco | 8122-64ehf-o | cpe:2.3:h:cisco:8122-64ehf-o |
| cisco | 8201 | cpe:2.3:h:cisco:8201 |
and 47 more
Versions reported by the vendor
Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.
Cisco Cisco IOS XR Software
- 24.2.1affected
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco ios xr24.2.1
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2020-3118Cisco IOS XR Software Cisco Discovery Protocol Format String VulnerabilityKEV69This week
- CVE-2020-3569Cisco IOS XR Software DVMRP Memory Exhaustion VulnerabilitiesKEV65This week
- CVE-2020-3566Cisco IOS XR Software DVMRP Memory Exhaustion VulnerabilityKEV65This week
Published before and after this one in the same product
- ← EarlierCVE-2024-20322Mar 13, 2024 · A vulnerability in the access control list (ACL) processing on Pseudowire interfaces in the ingress direction of Cisco IOS XR Software…23Monitor
- ← EarlierCVE-2024-20327Mar 13, 2024 · A vulnerability in the PPP over Ethernet (PPPoE) termination feature of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation…29Monitor
- Later →CVE-2024-20304Sep 11, 2024 · Cisco IOS XR Software Packet Memory Exhaustion Vulnerability30Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-24-0944 · Jul 16, 2024(Cisco IOS XR Güvenlik Bildirimi)
- TR-24-0940 · Jul 11, 2024(Cisco IOS XR Güvenlik Bildirimi)
Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- Administrator privileges are required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-732 · Incorrect Permission Assignment for Critical ResourceCVSS vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Accessing Functionality Not Properly Constrained by ACLsCAPEC-1likelihood: High · High
- Privilege AbuseCAPEC-122likelihood: High · Medium
- Directory IndexingCAPEC-127likelihood: High · Medium
- Using Malicious FilesCAPEC-17likelihood: High · Very High
- Exploiting Incorrectly Configured Access Control Security LevelsCAPEC-180likelihood: High · Medium
- Signing Malicious CodeCAPEC-206Very High
- Hijacking a privileged processCAPEC-234Medium
- Reusing Session IDs (aka Session Replay)CAPEC-60likelihood: High · High
ATT&CK techniques
- File and Directory DiscoveryT1083
- Access Token Manipulation:Token Impersonation/TheftT1134.001
- Server Software Component: Terminal Services DLLT1505.005
- Abuse Elevation Control MechanismT1548
- Use Alternate Authentication Material:Web Session CookieT1550.004
- Subvert Trust Controls:Code SigningT1553.002
- Compromise Client Software BinaryT1554
- Hijack Execution Flow:Executable Installer File Permissions WeaknessT1574.005
- Hijack Execution Flow: ServicesFile Permissions WeaknessT1574.010
Change log (0)
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.