CVE-2020-21526
CVE-2020-21526 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% (77th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Halo
- Published:
- Last modified:
Description
An Arbitrary file writing vulnerability in halo v1.1.3. In an interface to write files in the background, a directory traversal check is performed on the input path parameter, but the startsWith function can be used to bypass it.
Frequently asked questions
- What is CVE-2020-21526?
- An Arbitrary file writing vulnerability in halo v1.1.3. In an interface to write files in the background, a directory traversal check is performed on the input path parameter, but the startsWith function can be used to bypass it.
- How severe is CVE-2020-21526?
- CVE-2020-21526 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-2020-21526 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-21526?
- CVE-2020-21526 affects Halo. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-21526?
- 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-2020-21526 published?
- CVE-2020-21526 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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