CVE-2020-36401
CVE-2020-36401 is a high-severity vulnerability in Mruby with a CVSS 3.x base score of 7.8. 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-415.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 6.8
- EPSS exploit prediction: 1% (58th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-415
- Affected product: Mruby
- Published:
- Last modified:
Description
mruby 2.1.2 has a double free in mrb_default_allocf (called from mrb_free and obj_free).
Frequently asked questions
- What is CVE-2020-36401?
- mruby 2.1.2 has a double free in mrb_default_allocf (called from mrb_free and obj_free).
- How severe is CVE-2020-36401?
- CVE-2020-36401 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-36401 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-36401?
- CVE-2020-36401 affects Mruby. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-36401?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-36401 published?
- CVE-2020-36401 was published on 2021-07-01 and last updated on 2026-06-17.
References
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=23801
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/mruby/OSV-2020-744.yaml
- https://github.com/mruby/mruby/commit/97319697c8f9f6ff27b32589947e1918e3015503
Affected products (1)
- cpe:2.3:a:mruby:mruby:2.1.2:*:*:*:*:*:*:*
More vulnerabilities in Mruby
- CVE-2022-1286 — Critical (CVSS 9.8): heap-buffer-overflow in mrb_vm_exec in mruby/mruby in GitHub repository mruby/mruby prior to 3.2. Possible arbitrary…
- CVE-2022-1276 — Critical (CVSS 9.8): Out-of-bounds Read in mrb_get_args in GitHub repository mruby/mruby prior to 3.2. Possible arbitrary code execution if…
- CVE-2022-1212 — Critical (CVSS 9.8): Use-After-Free in str_escape in mruby/mruby in GitHub repository mruby/mruby prior to 3.2. Possible arbitrary code…
- CVE-2022-0631 — Critical (CVSS 9.8): Heap-based Buffer Overflow in Homebrew mruby prior to 3.2.
- CVE-2022-0570 — Critical (CVSS 9.8): Heap-based Buffer Overflow in Homebrew mruby prior to 3.2.
- CVE-2022-0080 — Critical (CVSS 9.8): mruby is vulnerable to Heap-based Buffer Overflow
Other CWE-415 (Double Free) vulnerabilities
- CVE-2018-0101 — Critical (CVSS 10.0): A vulnerability in the Secure Sockets Layer (SSL) VPN functionality of the Cisco Adaptive Security Appliance (ASA)…
- CVE-2026-8925 — Critical (CVSS 9.8): The curl logic that works with SASL authentication could end up cleaning up the GSASL context *twice* without clearing…
- CVE-2020-37239 — Critical (CVSS 9.8): libbabl 0.1.62 contains a broken double free detection vulnerability that allows attackers to bypass memory safety…
- CVE-2026-43414 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Completely fix fcport double…
- CVE-2026-43011 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When…
- CVE-2026-31609 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in…