Skip to content
Fencer Vulns
medium 5.3

CVE-2023-28120 json

Possible XSS Security Vulnerability in SafeBuffer#bytesplice

published 2023-03-15 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-1069 , GHSA-pj73-v5mw-pm9j

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 61%
public exploits
0
none known

Summary

There is a vulnerability in ActiveSupport if the new bytesplice method is called on a SafeBuffer with untrusted user input.

Patch / fix

  • rubygems activesupport 6.1.7.3, 7.0.4.3
  • activesupport_project activesupport 6.1.7.3, 7.0.4.3
  • rails activesupport 6.1.7.3, 7.0.4.3
  • rubyonrails activesupport 6.1.7.3, 7.0.4.3
  • rails Debian 14, Debian 13, Debian 12 2:6.1.7.3+dfsg-1

debian advisories DEBIAN-CVE-2023-28120

  • rmt-server SLE Module for Server Applications 15 SP5, SLE Module for Public Cloud 15 SP5, openSUSE Leap 15.5 2.13-150500.3.3.1
  • rmt-server SLES for SAP 15 SP1, SLES 15 SP1-LTSS, SLE Module for Public Cloud 15 SP1 +1 more 2.13-150100.3.45.1
  • rmt-server SLE Module for Server Applications 15 SP4, SLE Module for Public Cloud 15 SP4, openSUSE Leap 15.4 2.13-150400.3.12.1
  • rmt-server SLES for SAP 15 SP2, SLES 15 SP2-LTSS, SLE Module for Public Cloud 15 SP2 +2 more 2.13-150200.3.32.1
  • rmt-server SLES for SAP 15 SP3, SLES 15 SP3-LTSS, SLE Real Time 15 SP3 +6 more 2.13-150300.3.24.1

suse advisories SUSE-SU-2023:2781-1SUSE-SU-2023:2304-1SUSE-SU-2023:2295-1SUSE-SU-2023:2294-1SUSE-SU-2023:2280-1

  • rubygem-activesupport-7.0 openSUSE Tumbleweed 7.0.8.6-1.3
  • rubygem-activesupport-7.0 openSUSE Tumbleweed 7.0.8.4-1.1
  • rubygem-activesupport-7.0 openSUSE Tumbleweed 7.0.4.3-1.1
  • rmt-server openSUSE Tumbleweed 2.12-1.1

opensuse advisories openSUSE-SU-2025:15114-1openSUSE-SU-2024:14071-1openSUSE-SU-2024:12804-1openSUSE-SU-2024:12886-1

  • ruby-activesupport Alpine 3.24, Alpine 3.23, Alpine 3.22 +5 more 7.0.4.3-r0

alpine advisories ALPINE-CVE-2023-28120

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-28120 updated cvss 6.1

rubygem-activesupport: Possible XSS in SafeBuffer#bytesplice

  • Red Hat 3scale API Management Platform 2 3scale-amp2/zync-rhel8, 3scale-amp2/backend-rhel8, 3scale-amp2/toolbox-rhel8
    affected: workaround, no fix available, no fix planned “Avoid calling bytesplice on a SafeBuffer (html_safe) string with untrusted user input.”
  • Red Hat OpenShift Container Platform 3.11 rubygem-activesupport
    affected: workaround, no fix planned “Avoid calling bytesplice on a SafeBuffer (html_safe) string with untrusted user input.”
  • Red Hat RHOL 5.6 for RHEL 8 openshift-logging/fluentd-rhel8 v1.14.6-113
    fixed: vendor fix “Avoid calling bytesplice on a SafeBuffer (html_safe) string with untrusted user input.” RHSA-2023:1953
  • Red Hat RHOL 5.7 for RHEL 8 openshift-logging/fluentd-rhel8 v1.14.6-140
    fixed: vendor fix “Avoid calling bytesplice on a SafeBuffer (html_safe) string with untrusted user input.” RHSA-2023:3495
  • Red Hat Satellite 6 candlepin, candlepin-selinux, rubygem-activesupport, rubygem-deep_cloneable Red Hat RHOL 5.6 for RHEL 8 openshift-logging/vector-rhel8 v0.21.0-77, openshift-logging/kibana6-rhel8 v6.8.1-350, openshift-logging/logging-loki-rhel8 v2.7.4-6, openshift-logging/eventrouter-rhel8 v0.4.0-106, openshift-logging/loki-rhel8-operator v5.6.5-6, openshift-logging/opa-openshift-rhel8 v0.1.0-71, +11 more Red Hat RHOL 5.7 for RHEL 8 openshift-logging/vector-rhel8 v0.21.0-94, openshift-logging/kibana6-rhel8 v6.8.1-363, openshift-logging/eventrouter-rhel8 v0.4.0-141, openshift-logging/logging-loki-rhel8 v2.8.0-18, openshift-logging/loki-rhel8-operator v5.7.2-12, openshift-logging/opa-openshift-rhel8 v0.1.0-99, +11 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
21 mo ago

Exploit prediction

0.95% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
GitHub 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
rubygems activesupport
>=7.0.0, <7.0.4.3
<6.1.7.3
7.0.4.3
6.1.7.3

Affected products

  • Rails ActiveSupport

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.