What is CVE-2018-21018?

CVE-2018-21018 is a critical-severity vulnerability in Joinmastodon Mastodon, classified under Insufficient Session Expiration. CVSS score: 9.8/10. Published 2019-09-22.

How severe is CVE-2018-21018?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2018-21018 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Joinmastodon Mastodon

CVE-2018-21018

Mastodon before 2.6.3 mishandles timeouts of incompletely established sessions.

EPSS: 0.026 (83.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Joinmastodon Mastodon
N/a — versions n/a

Weakness classification (CWE)

CWE-613 — Insufficient Session Expiration

Public proof-of-concept exploits

References

cve@mitre.org (Third Party Advisory, x_refsource_MISC, Release Notes)
cve@mitre.org (Third Party Advisory, x_refsource_MISC, Release Notes)
cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)

Frequently asked questions

What is CVE-2018-21018?: CVE-2018-21018 is a critical-severity vulnerability in Joinmastodon Mastodon, classified under Insufficient Session Expiration. CVSS score: 9.8/10. Published 2019-09-22.
How severe is CVE-2018-21018?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2018-21018 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.