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, SafeBuffer#% does not propagate the @html_unsafe flag to the newly created buffer. If a SafeBuffer is mutated in place (e.g. via gsub!) and then formatted with % using untrusted arguments, the result incorrectly reports html_safe? == true, bypassing ERB auto-escaping and possibly leading to XSS. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
CVE-2026-33170
This medium-severity CVE scores 6.1 under NVD CVSS v3. EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.1
- EG Score
- 6.1(low)
- EG Risk
- 32(Track)EG Risk 32/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity61% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 25%
- KEV
- Not listed
Published
March 24, 2026
Last Modified
June 17, 2026
References (7)
- security-advisories@githubhttps://github.com/rails/rails/commit/50d732af3b7c8aaf63cbcca0becbc00279b215b7
- security-advisories@githubhttps://github.com/rails/rails/commit/6e8a81108001d58043de9e54a06fca58962fc2db
- security-advisories@githubhttps://github.com/rails/rails/commit/c1ad0e8e1972032f3395853a5e99cea035035beb
- security-advisories@githubhttps://github.com/rails/rails/releases/tag/v7.2.3.1
- security-advisories@githubhttps://github.com/rails/rails/releases/tag/v8.0.4.1
- security-advisories@githubhttps://github.com/rails/rails/releases/tag/v8.1.2.1
- security-advisories@githubhttps://github.com/rails/rails/security/advisories/GHSA-89vf-4333-qx8v
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 4× in last 7d / 4× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:28 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-27 14:31 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-33170?
When was CVE-2026-33170 disclosed?
Is CVE-2026-33170 actively exploited?
What is the CVSS score of CVE-2026-33170?
How do I remediate CVE-2026-33170?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-33170
Is Your Infrastructure Affected by CVE-2026-33170?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.