CVE-2025-27788 | Ruby JSON Parser has Out-of-bounds Read

JSON is a JSON implementation for Ruby. Starting in version 2.10.0 and prior to version 2.10.2, a specially crafted document could cause an out of bound read, most likely resulting in a crash. Versions prior to 2.10.0 are not vulnerable. Version 2.10.2 fixes the problem. No known workarounds are available.

Published: 2025-03-12 Last update: 2025-04-02 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-27788 is rated Moderate Risk (42.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.16%). 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-2025-27788

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 2026-05-04 0.10% 0.16% +0.06%
2 2026-04-20 0.37% 0.10% -0.27%
3 2026-01-06 — 0.37% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-27788

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:N/A:H 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-27788

GitHub Security Advisory for CVE-2025-27788

GHSA-9m3q-rhmv-5q44 · Severity: high · Ecosystem: rubygems — Out-of-bounds Read in Ruby JSON Parser

OS Trackers for CVE-2025-27788

vendor priority summary link
debian unimportant CVE-2025-27788 unimportant priority: Debian including 1 source packages (ruby-json), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-27788
redhat high — https://access.redhat.com/security/cve/CVE-2025-27788
ubuntu medium CVE-2025-27788 medium priority: Ubuntu including 1 source packages (ruby-json), 9 status rows across 9 suites (bionic, focal, jammy, noble, oracular, plucky, trusty, upstream, xenial): not-affected 7, ignored 1, released 1. https://ubuntu.com/security/CVE-2025-27788

Affected software / configurations for CVE-2025-27788

Vendor Product Version Raw CPE
ruby-lang javascript_object_notation >= 2.10.0, < 2.10.2 cpe:2.3:a:ruby-lang:javascript_object_notation:*:*:*:*:*:ruby:*:*

References for CVE-2025-27788

cvelogic Threat Intelligence