CVE-2020-11498
CVE-2020-11498 is a high-severity vulnerability in Slack Nebula with a CVSS 3.x base score of 8.8. 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: High (CVSS 3.x base score 8.8)
- CVSS v2: 8.5
- EPSS exploit prediction: 3% (87th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Slack Nebula
- Published:
- Last modified:
Description
Slack Nebula through 1.1.0 contains a relative path vulnerability that allows a low-privileged attacker to execute code in the context of the root user via tun_darwin.go or tun_windows.go. A user can also use Nebula to execute arbitrary code in the user's own context, e.g., for user-level persistence or to bypass security controls. NOTE: the vendor states that this "requires a high degree of access and other preconditions that are tough to achieve."
Frequently asked questions
- What is CVE-2020-11498?
- Slack Nebula through 1.1.0 contains a relative path vulnerability that allows a low-privileged attacker to execute code in the context of the root user via tun_darwin.go or tun_windows.go. A user can also use Nebula to execute arbitrary code in the user's own context, e.g., for user-level persistence or to bypass security controls. NOTE: the vendor states that this "requires a high degree of access and other preconditions that are tough to achieve."
- How severe is CVE-2020-11498?
- CVE-2020-11498 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-11498 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-11498?
- CVE-2020-11498 affects Slack Nebula. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-11498?
- 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-2020-11498 published?
- CVE-2020-11498 was published on 2020-04-02 and last updated on 2026-06-17.
References
- http://www.pwn3d.org/posts/7918501-slack-nebula-relative-path-bug-bounty-disclosure
- https://github.com/slackhq/nebula/pull/191
Affected products (1)
- cpe:2.3:a:slack:nebula:*:*:*:*:*:*:*:*
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