CVE-2020-26261 Vulnerability Analysis & Exploit Details

CVE-2020-26261
Vulnerability Scoring

7.9
/10
Very High Risk

Highly exploitable, CVE-2020-26261 poses a critical security risk that could lead to severe breaches.

Attack Complexity Details

  • Attack Complexity: Low
    Exploits can be performed without significant complexity or special conditions.
  • Attack Vector: Local
    Vulnerability requires local system access.
  • Privileges Required: Low
    Some privileges are necessary to exploit the vulnerability.
  • Scope: Changed
    Successful exploitation can impact components beyond the vulnerable component.
  • User Interaction: Required
    User interaction is necessary for successful exploitation.

CVE-2020-26261 Details

Status: Analyzed

Last updated: 🕤 10 Dec 2020, 21:46 UTC
Originally published on: 🕔 09 Dec 2020, 17:15 UTC

Time between publication and last update: 1 days

CVSS Release: version 3

CVSS3 Source

nvd@nist.gov

CVSS3 Type

Primary

CVSS3 Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

CVE-2020-26261 Vulnerability Summary

CVE-2020-26261: jupyterhub-systemdspawner enables JupyterHub to spawn single-user notebook servers using systemd. In jupyterhub-systemdspawner before version 0.15 user API tokens issued to single-user servers are specified in the environment of systemd units. These tokens are incorrectly accessible to all users. In particular, the-littlest-jupyterhub is affected, which uses systemdspawner by default. This is patched in jupyterhub-systemdspawner v0.15

Assessing the Risk of CVE-2020-26261

Access Complexity Graph

The exploitability of CVE-2020-26261 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2020-26261

CVE-2020-26261 presents an accessible attack vector with minimal effort required. Restricting access controls and implementing security updates are critical to reducing exploitation risks.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2020-26261, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2020-26261, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: High
    Exploiting CVE-2020-26261 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2020-26261 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: None
    CVE-2020-26261 does not impact system availability.

Exploit Prediction Scoring System (EPSS)

The EPSS score estimates the probability that this vulnerability will be exploited in the near future.

EPSS Score: 0.045% (probability of exploit)

EPSS Percentile: 18.38% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 81.62% of others.

CVE-2020-26261 References

External References

CWE Common Weakness Enumeration

CWE-668

Vulnerable Configurations

  • cpe:2.3:a:jupyterhub:systemdspawner:0.9:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.1:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.1:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.5:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.5:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.6:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.6:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.7:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.7:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.8:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.8:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.9:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.9:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.10:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.10:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.11:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.11:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.9.12:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.9.12:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.10:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.10:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.11:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.11:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.12:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.12:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.13:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.13:*:*:*:*:*:*:*
  • cpe:2.3:a:jupyterhub:systemdspawner:0.14:*:*:*:*:*:*:*
    cpe:2.3:a:jupyterhub:systemdspawner:0.14:*:*:*:*:*:*:*

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