CVE-2020-35863
CVE-2020-35863 is a critical-severity vulnerability in Hyper 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-444.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 3% (85th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-444
- Affected product: Hyper
- Published:
- Last modified:
Description
An issue was discovered in the hyper crate before 0.12.34 for Rust. HTTP request smuggling can occur. Remote code execution can occur in certain situations with an HTTP server on the loopback interface.
Frequently asked questions
- What is CVE-2020-35863?
- An issue was discovered in the hyper crate before 0.12.34 for Rust. HTTP request smuggling can occur. Remote code execution can occur in certain situations with an HTTP server on the loopback interface.
- How severe is CVE-2020-35863?
- CVE-2020-35863 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-2020-35863 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-35863?
- CVE-2020-35863 affects Hyper. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-35863?
- 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-2020-35863 published?
- CVE-2020-35863 was published on 2020-12-31 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:hyper:hyper:*:*:*:*:*:rust:*:*
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