On 20December 2023, Ivanti announced that 20 vulnerabilities in Ivanti Avalanche On-Prem were patched in the product’s latest update. Arctic Wolf has highlighted 13 of these vulnerabilities in this bulletin that were rated as critical severity and could lead to remote code execution (RCE) or Denial of Service (DoS).
| CVE-ID | Vulnerability Type | CVSS Score |
| CVE-2023-41727 | Unauthenticated Buffer Overflow | 9.8 – Critical |
| CVE-2023-46216 | Unauthenticated Buffer Overflow | 9.8 – Critical |
| CVE-2023-46217 | Unauthenticated Buffer Overflow | 9.8 – Critical |
| CVE-2023-46220 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46221 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46222 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46223 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46224 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46225 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46257 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46258 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46259 | Stack-based Buffer Overflow RCE | 9.8 – Critical |
| CVE-2023-46261 | Heap-based Buffer Overflow RCE | 9.8 – Critical |
These vulnerabilities were discovered by researchers at Tenable and Trend Micro’s Zero Day Initiative and responsibly disclosed to Ivanti. At this time, there have been no public proof of concept (PoC) exploit code published or active exploitation for these vulnerabilities observed in the wild. However, given the past history of Ivanti products being targeted by threat actors (as evidenced by CISA’s known exploited vulnerabilities catalog and AW Labs security bulletin), we expect that threat actors are likely to attempt exploitation in the near term of one or more of the vulnerabilities described in this bulletin.
Recommendation for CVE-2023-41727, CVE-2023-46220, CVE-2023-46261
Upgrade Ivanti Avalanche to Fixed Version
Arctic Wolf strongly recommends upgrading Ivanti Avalanche to the latest fixed version.
| Product | Affected Version(s) | Fixed Version |
| Ivanti Avalanche |
|
6.4.2 |
Please follow your organisation’s patching and testing guidelines to avoid operational impact.
