CVE-2020-21522
CVE-2020-21522 is a critical-severity vulnerability in Halo with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 2% (72nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Halo
- Published:
- Last modified:
Description
An issue was discovered in halo V1.1.3. A Zip Slip Directory Traversal Vulnerability in the backend,the attacker can overwrite some files, such as ftl files, .bashrc files in the user directory, and finally get the permissions of the operating system.
Frequently asked questions
- What is CVE-2020-21522?
- An issue was discovered in halo V1.1.3. A Zip Slip Directory Traversal Vulnerability in the backend,the attacker can overwrite some files, such as ftl files, .bashrc files in the user directory, and finally get the permissions of the operating system.
- How severe is CVE-2020-21522?
- CVE-2020-21522 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-21522 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-21522?
- CVE-2020-21522 affects Halo. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-21522?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2020-21522 published?
- CVE-2020-21522 was published on 2020-09-30 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:halo:halo:1.1.3:*:*:*:*:*:*:*
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