CVE-2026-33176

Rails Active Support has a possible DoS vulnerability in its number helpers

6.6 MediumFix available

Active Support is a toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, Active Support number helpers accept strings containing scientific notation (e.g. 1e10000), which BigDecimal expands into extremely large decimal representations. This can cause excessive memory allocation and CPU consumption when the expanded number is formatted, possibly resulting in a DoS vulnerability. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

0.86%Up 0.8 points since Mar 24, 2026

What each source reports

CVE List Score used 6.6

Rails Active Support has a possible DoS vulnerability in its number helpers

Record: CVE-2026-33176
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

EUVDEUVD-2026-14630 6.6

Record: EUVD-2026-14630
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Updated: 2026-11-02

GitHub AdvisoriesGHSA-2j26-frm8-cmj9 6.6

Rails Active Support has a possible DoS vulnerability in its number helpers

Impact

Active Support number helpers accept strings containing scientific notation (e.g. 1e10000), which when converted to a string could be expanded into extremely large decimal representations. This can cause excessive memory allocation and CPU consumption when the expanded number is formatted, possibly resulting in a DoS vulnerability.

Releases

The fixed releases are available at the normal locations.

Credit

This issue was responsibly reported by Hackerone researcher manun.

Record: GHSA-2j26-frm8-cmj9
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

NVD 6.6

Record: CVE-2026-33176
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

OSV 6.6

Rails Active Support has a possible DoS vulnerability in its number helpers

Record: CVE-2026-33176
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

OSVDEBIAN-CVE-2026-33176 7.5

Record: DEBIAN-CVE-2026-33176
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

Show 5 moreShow less

OSVGHSA-2j26-frm8-cmj9 6.6

Rails Active Support has a possible DoS vulnerability in its number helpers

Impact

Releases

The fixed releases are available at the normal locations.

Credit

This issue was responsibly reported by Hackerone researcher manun.

Record: GHSA-2j26-frm8-cmj9
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness: CWE-400, CWE-770
Updated: 2026-11-02

OSVRHSA-2026:14835 8.5

Red Hat Security Advisory: Satellite 6.18.5 Async Update

Record: RHSA-2026:14835
CVSS 3.1: 8.5 HighCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Updated: 2026-11-02

OSVRHSA-2026:14873 8.3

Red Hat Security Advisory: Satellite 6.17.8 Async Update

Record: RHSA-2026:14873
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
Updated: 2026-11-02

OSVRHSA-2026:14874 8.3

Red Hat Security Advisory: Satellite 6.16.8 Async Update

Record: RHSA-2026:14874
CVSS 3.1: 8.3 HighCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
Updated: 2026-11-02

OSVUBUNTU-CVE-2026-33176 6.6

Record: UBUNTU-CVE-2026-33176
CVSS 4.0: 6.6 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`activesupport` RubyGems	8.1.0.beta1 up to 8.1.2.1	8.1.2.1
`activesupport` RubyGems	8.0.0.beta1 up to 8.0.4.1	8.0.4.1
`activesupport` RubyGems	before 7.2.3.1	7.2.3.1
`rails` Debian:12	before 2:6.1.7.10+dfsg-1~deb12u3, plus listed versions 2:6.1.7.10+dfsg-1~deb12u12:6.1.7.10+dfsg-1~deb12u22:6.1.7.3+dfsg-12:6.1.7.3+dfsg-102:6.1.7.3+dfsg-11 Show 12 moreShow less 2:6.1.7.3+dfsg-122:6.1.7.3+dfsg-132:6.1.7.3+dfsg-22:6.1.7.3+dfsg-2~deb12u12:6.1.7.3+dfsg-32:6.1.7.3+dfsg-42:6.1.7.3+dfsg-52:6.1.7.3+dfsg-62:6.1.7.3+dfsg-72:6.1.7.3+dfsg-7~exp12:6.1.7.3+dfsg-82:6.1.7.3+dfsg-9	2:6.1.7.10+dfsg-1~deb12u3
`rails` Debian:13	before 2:7.2.2.2+dfsg-2~deb13u2, plus listed versions 2:7.2.2.1+dfsg-72:7.2.2.2+dfsg-12:7.2.2.2+dfsg-2~deb13u1	2:7.2.2.2+dfsg-2~deb13u2
`rails` Debian:14	before 2:7.2.3.1+dfsg-1, plus listed versions 2:7.2.2.1+dfsg-72:7.2.2.2+dfsg-12:7.2.2.2+dfsg-22:7.2.2.2+dfsg-2~deb13u12:7.2.2.2+dfsg-2~deb13u22:7.2.3+dfsg-12:7.2.3+dfsg-22:7.2.3+dfsg-3	2:7.2.3.1+dfsg-1
`activesupport` RubyGems	8.1.0.beta1 up to 8.1.2.1, plus listed versions 8.1.08.1.0.rc18.1.18.1.2	8.1.2.1
`activesupport` RubyGems	8.0.0.beta1 up to 8.0.4.1, plus listed versions 8.0.08.0.0.18.0.0.rc18.0.0.rc28.0.1 Show 4 moreShow less 8.0.28.0.2.18.0.38.0.4	8.0.4.1
`activesupport` RubyGems	before 7.2.3.1, plus listed versions 1.0.01.0.11.0.21.0.31.0.4 Show 45 moreShow less 1.1.01.1.11.2.11.2.21.2.31.2.41.2.51.3.01.3.11.4.01.4.11.4.21.4.31.4.42.0.02.0.12.0.22.0.42.0.52.1.02.1.12.1.22.2.22.2.32.3.102.3.112.3.122.3.142.3.152.3.162.3.172.3.182.3.22.3.32.3.42.3.52.3.62.3.6.pre2.3.72.3.82.3.8.pre12.3.92.3.9.pre3.0.03.0.0.beta	7.2.3.1
`python3.12-django` Red Hat:satellite_capsule:6.18::el9 From an advisory covering 8 CVEs	before 0:4.2.30-1.el9pc	0:4.2.30-1.el9pc

Show 75 moreShow less

Affected packages
Package	Affected	Fixed
`python3.12-django` Red Hat:satellite:6.18::el9 From an advisory covering 8 CVEs	before 0:4.2.30-1.el9pc	0:4.2.30-1.el9pc
`python3.12-markdown` Red Hat:satellite_capsule:6.18::el9 From an advisory covering 8 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.12-markdown` Red Hat:satellite:6.18::el9 From an advisory covering 8 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.12-pyOpenSSL` Red Hat:satellite_capsule:6.18::el9 From an advisory covering 8 CVEs	before 0:26.0.0-2.el9pc	0:26.0.0-2.el9pc
`python3.12-pyOpenSSL` Red Hat:satellite:6.18::el9 From an advisory covering 8 CVEs	before 0:26.0.0-2.el9pc	0:26.0.0-2.el9pc
`rubygem-activesupport` Red Hat:satellite_capsule:6.18::el9 From an advisory covering 8 CVEs	before 0:7.0.8.7-2.el9sat	0:7.0.8.7-2.el9sat
`rubygem-activesupport` Red Hat:satellite:6.18::el9 From an advisory covering 8 CVEs	before 0:7.0.8.7-2.el9sat	0:7.0.8.7-2.el9sat
`python-markdown` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.11-markdown` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python-markdown` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.11-markdown` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python-pillow` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow-debugsource` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow-debuginfo` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow-debugsource` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow-debuginfo` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pyOpenSSL` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:25.1.0-0.3.el9pc	0:25.1.0-0.3.el9pc
`python3.11-pyOpenSSL` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:25.1.0-0.3.el9pc	0:25.1.0-0.3.el9pc
`python-pyOpenSSL` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:25.1.0-0.3.el9pc	0:25.1.0-0.3.el9pc
`python3.11-pyOpenSSL` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:25.1.0-0.3.el9pc	0:25.1.0-0.3.el9pc
`candlepin` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:4.4.25-1.el9sat	0:4.4.25-1.el9sat
`candlepin-selinux` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:4.4.25-1.el9sat	0:4.4.25-1.el9sat
`rubygem-activesupport` Red Hat:satellite_capsule:6.17::el9 From an advisory covering 5 CVEs	before 0:7.0.8.7-2.el9sat	0:7.0.8.7-2.el9sat
`rubygem-activesupport` Red Hat:satellite:6.17::el9 From an advisory covering 5 CVEs	before 0:7.0.8.7-2.el9sat	0:7.0.8.7-2.el9sat
`python-markdown` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:3.8.2-1.el8pc	0:3.8.2-1.el8pc
`python3.11-markdown` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:3.8.2-1.el8pc	0:3.8.2-1.el8pc
`python-markdown` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:3.8.2-1.el8pc	0:3.8.2-1.el8pc
`python3.11-markdown` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:3.8.2-1.el8pc	0:3.8.2-1.el8pc
`python-markdown` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.11-markdown` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python-markdown` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python3.11-markdown` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:3.8.2-1.el9pc	0:3.8.2-1.el9pc
`python-pillow` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python-pillow-debugsource` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python3.11-pillow` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python3.11-pillow-debuginfo` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python-pillow` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python-pillow-debugsource` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python3.11-pillow` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python3.11-pillow-debuginfo` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:12.1.1-1.el8pc	0:12.1.1-1.el8pc
`python-pillow` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow-debugsource` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow-debuginfo` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pillow-debugsource` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python3.11-pillow-debuginfo` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:12.1.1-1.el9pc	0:12.1.1-1.el9pc
`python-pyOpenSSL` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:24.1.0-2.el8pc	0:24.1.0-2.el8pc
`python3.11-pyOpenSSL` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:24.1.0-2.el8pc	0:24.1.0-2.el8pc
`python-pyOpenSSL` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:24.1.0-2.el8pc	0:24.1.0-2.el8pc
`python3.11-pyOpenSSL` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:24.1.0-2.el8pc	0:24.1.0-2.el8pc
`python-pyOpenSSL` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:24.1.0-2.el9pc	0:24.1.0-2.el9pc
`python3.11-pyOpenSSL` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:24.1.0-2.el9pc	0:24.1.0-2.el9pc
`python-pyOpenSSL` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:24.1.0-2.el9pc	0:24.1.0-2.el9pc
`python3.11-pyOpenSSL` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:24.1.0-2.el9pc	0:24.1.0-2.el9pc
`candlepin` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:4.4.25-1.el8sat	0:4.4.25-1.el8sat
`candlepin-selinux` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:4.4.25-1.el8sat	0:4.4.25-1.el8sat
`candlepin` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:4.4.25-1.el9sat	0:4.4.25-1.el9sat
`candlepin-selinux` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:4.4.25-1.el9sat	0:4.4.25-1.el9sat
`rubygem-activesupport` Red Hat:satellite_capsule:6.16::el8 From an advisory covering 5 CVEs	before 0:6.1.7.8-2.el8sat	0:6.1.7.8-2.el8sat
`rubygem-activesupport` Red Hat:satellite:6.16::el8 From an advisory covering 5 CVEs	before 0:6.1.7.8-2.el8sat	0:6.1.7.8-2.el8sat
`rubygem-activesupport` Red Hat:satellite_capsule:6.16::el9 From an advisory covering 5 CVEs	before 0:6.1.7.8-2.el9sat	0:6.1.7.8-2.el9sat
`rubygem-activesupport` Red Hat:satellite:6.16::el9 From an advisory covering 5 CVEs	before 0:6.1.7.8-2.el9sat	0:6.1.7.8-2.el9sat
`rails` Ubuntu:Pro:16.04:LTS	All versions, plus listed versions 2:4.1.10-12:4.2.5-12:4.2.5.1-12:4.2.5.2-22:4.2.6-12:4.2.6-1ubuntu0.1~esm12:4.2.6-1ubuntu0.1~esm2	None known
`rails` Ubuntu:Pro:18.04:LTS	All versions, plus listed versions 2:4.2.9-22:4.2.9-42:4.2.10-0ubuntu42:4.2.10-0ubuntu4+esm12:4.2.10-0ubuntu4+esm2	None known
`rails` Ubuntu:Pro:20.04:LTS	All versions, plus listed versions 2:5.2.2.1+dfsg-1ubuntu12:5.2.3+dfsg-32:5.2.3+dfsg-3ubuntu0.1~esm1	None known
`rails` Ubuntu:Pro:22.04:LTS	All versions, plus listed versions 2:6.0.3.7+dfsg-22:6.1.4.1+dfsg-8ubuntu22:6.1.4.1+dfsg-8ubuntu2+esm1	None known
`rails` Ubuntu:24.04:LTS	All versions, plus listed versions 2:6.1.7.3+dfsg-2build12:6.1.7.3+dfsg-3	None known
`rails` Ubuntu:25.10	All versions, plus listed versions 2:6.1.7.3+dfsg-72:7.2.2.1+dfsg-7	None known
`rails` Ubuntu:26.10	All versions, plus listed versions 2:7.2.3+dfsg-22:7.2.3.2+dfsg-2	None known
`rails` Ubuntu:26.04:LTS	All versions, plus listed versions 2:7.2.2.1+dfsg-72:7.2.2.2+dfsg-22:7.2.3+dfsg-2	None known

History

History
Recorded	Changed	Sources
Nov 6, 2026	affected, facts
Nov 2, 2026	first indexed	CVE List, EUVD, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-33176 is a medium vulnerability (CVSS 6.6) in Rubyonrails Rails, published March 23, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.86%, the 58th percentile. Fixed in activesupport 8.1.2.1.

References

Show 108 moreShow less

This page doesn't list everything

Left out here: 432 versions. The JSON record has them.