Concrete CMS 9 before 9.5.0 is vulnerable to Cross Site Request Forgery (CSRF) at concrete/controllers/backend/file approveVersion(). The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
CVE-2026-8435
This medium-severity CVE scores 6.5 under NVD CVSS v3. EPSS exploit probability: 0.1%, top 98% of all CVEs by exploit prediction. 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
- 6.5
- EG Score
- 6.5(medium)
- EPSS
- 1.8%
- KEV
- Not listed
Published
May 21, 2026
Last Modified
May 22, 2026
Advisory Details (1)
Auto-updated Jun 14, 20269.5.1 Release Notes :: Concrete CMS
https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notesVendor Advisories for CVE-2026-8435(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
Packagist(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| concrete5/concrete5 | 9.0.0 ... 9.5.0RC2 (45 versions) | 9.5.1 | — |
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 46× 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.
- 2026-07-11 08:27 UTCEPSS rescore
- 2026-07-09 19:10 UTCEPSS rescore
- 2026-07-08 15:16 UTCEPSS rescore
- 2026-07-07 13:46 UTCEPSS rescore
- 2026-07-07 13:46 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-05 02:31 UTCEPSS rescore
- 2026-07-05 02:30 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-01 15:07 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-29 16:41 UTCEG score recompute
- 2026-06-28 14:07 UTCEPSS rescore
- 2026-06-28 04:56 UTCEPSS rescore
- 2026-06-27 21:17 UTCEG score recompute
- 2026-06-27 03:08 UTCEPSS rescore
- 2026-06-26 19:16 UTCEG score recompute
- 2026-06-25 14:11 UTCEG score recompute
- 2026-06-25 13:50 UTCEPSS rescore
- 2026-06-23 21:33 UTCEPSS rescore
- 2026-06-22 14:25 UTCEPSS rescore
- 2026-06-21 14:56 UTCEPSS rescore
- 2026-06-21 01:59 UTCEPSS rescore
Show 63 moreShow fewer
- 2026-06-19 19:26 UTCEPSS rescore
- 2026-06-18 17:52 UTCEPSS rescore
- 2026-06-17 17:53 UTCEPSS rescore
- 2026-06-17 12:44 UTCEG score recompute
- 2026-06-17 12:44 UTCGHSA enrichment
- 2026-06-16 10:32 UTCEG score recompute
- 2026-06-16 10:32 UTCGHSA enrichment
- 2026-06-15 17:49 UTCEPSS rescore
- 2026-06-15 17:49 UTCEPSS rescore
- 2026-06-15 07:50 UTCEG score recompute
- 2026-06-15 07:50 UTCGHSA enrichment
- 2026-06-14 23:18 UTCEPSS rescore
- 2026-06-14 05:22 UTCEG score recompute
- 2026-06-14 05:22 UTCGHSA enrichment
- 2026-06-13 23:00 UTCEPSS rescore
- 2026-06-13 03:24 UTCEG score recompute
- 2026-06-13 03:24 UTCGHSA enrichment
- 2026-06-12 23:12 UTCEPSS rescore
- 2026-06-12 23:12 UTCEPSS rescore
- 2026-06-12 01:09 UTCEG score recompute
- 2026-06-12 01:09 UTCGHSA enrichment
- 2026-06-11 14:00 UTCEPSS rescore
- 2026-06-10 23:18 UTCEG score recompute
- 2026-06-10 23:18 UTCGHSA enrichment
- 2026-06-10 22:19 UTCEPSS rescore
- 2026-06-10 13:22 UTCEPSS rescore
- 2026-06-09 21:28 UTCEG score recompute
- 2026-06-09 21:28 UTCGHSA enrichment
- 2026-06-08 19:20 UTCEG score recompute
- 2026-06-08 19:20 UTCGHSA enrichment
- 2026-06-08 14:17 UTCEPSS rescore
- 2026-06-07 15:25 UTCEPSS rescore
- 2026-06-07 13:40 UTCEG score recompute
- 2026-06-07 13:40 UTCGHSA enrichment
- 2026-06-06 13:47 UTCEPSS rescore
- 2026-06-06 11:50 UTCEG score recompute
- 2026-06-06 11:50 UTCGHSA enrichment
- 2026-06-05 22:47 UTCEPSS rescore
- 2026-06-05 09:59 UTCEG score recompute
- 2026-06-05 09:59 UTCGHSA enrichment
- 2026-06-05 06:10 UTCEPSS rescore
- 2026-06-04 13:12 UTCEPSS rescore
- 2026-06-04 08:08 UTCEG score recompute
- 2026-06-04 08:08 UTCGHSA enrichment
- 2026-06-03 06:16 UTCEG score recompute
- 2026-06-03 06:16 UTCGHSA enrichment
- 2026-06-02 20:13 UTCEPSS rescore
- 2026-06-02 04:25 UTCEG score recompute
- 2026-06-02 04:25 UTCGHSA enrichment
- 2026-06-01 13:52 UTCEPSS rescore
- 2026-06-01 02:34 UTCEG score recompute▲ 4.20
- 2026-06-01 02:34 UTCGHSA enrichment
- 2026-05-31 22:30 UTCEPSS rescore
- 2026-05-31 00:16 UTCEPSS rescore
- 2026-05-29 13:44 UTCEPSS rescore
- 2026-05-28 13:44 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-26 13:44 UTCEPSS rescore
- 2026-05-26 07:18 UTCEPSS rescore
- 2026-05-23 00:07 UTCEG score recompute
- 2026-05-22 22:08 UTCEG score recompute
- 2026-05-21 22:44 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-8435?
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What is the CVSS score of CVE-2026-8435?
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Dependency Blast Radius
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