CVE-2019-18848

The json-jwt gem before 1.11.0 for Ruby lacks an element count during the splitting of a JWE string.

Published: 2019-11-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2019-18848 is rated Moderate Risk (54/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.26%). Core evidence: EPSS rose +1.05% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-18848

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.21% 1.26% +1.05%
2 2026-02-16 0.48% 0.21% -0.28%
3 2025-06-06 0.48%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-18848

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2019-18848

GitHub Security Advisory for CVE-2019-18848

GHSA-cff7-6h4q-q5pj · Severity: high · Ecosystem: rubygems — JSON-jwt Gem lacked element count during splitting of JWE string

OS Trackers for CVE-2019-18848

vendor priority summary link
debian not yet assigned CVE-2019-18848 not yet assigned priority: Debian including 1 source packages (ruby-json-jwt), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2019-18848
ubuntu medium CVE-2019-18848 medium priority: Ubuntu including 1 source packages (ruby-json-jwt), 18 status rows across 18 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 12, DNE 2, ignored 2, needed 1, released 1. https://ubuntu.com/security/CVE-2019-18848

Affected software / configurations for CVE-2019-18848

Vendor Product Version Raw CPE
json-jwt_project json-jwt < 1.11.0 cpe:2.3:a:json-jwt_project:json-jwt:*:*:*:*:*:ruby:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

References for CVE-2019-18848

cvelogic Threat Intelligence