CVE-2021-34857 json
This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.1.3 (49160).
published 2021-10-25 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21504
- cvss
- 8.2
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 19%
- public exploits
- 0
- none known
Summary
This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.1.3 (49160). An attacker must first obtain the ability to execute high-privileged code on the target guest system in order to exploit this vulnerability. The specific flaw exists within the Toolgate component. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the hypervisor. Was ZDI-CAN-13601.
Patch / fix
- kb.parallels.com/125013 advisory
Exploit prediction
0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.2 | CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVD | 2.0 | 4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- Parallels Desktop
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
kb.parallels.com
/125013
patch, vendor-advisory
-
zerodayinitiative.com
/advisories/ZDI-21-940/
third-party-advisory, vdb-entry
Sources
- CVE List CVE-2021-34857
- NVD CVE-2021-34857
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