Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, when the patreon_webhook_secret site setting is blank, an attacker can forge valid webhook signatures by computing an HMAC-MD5 with an empty string as the key. Since the request body is known to the sender, the attacker can produce a matching signature and send arbitrary webhook payloads. This allows unauthorized creation, modification, or deletion of Patreon pledge data and triggering patron-to-group synchronization. This vulnerability is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0. The fix rejects webhook requests when the webhook secret is not configured, preventing signature forgery with an empty key. As a workaround, configure the patreon_webhook_secret site setting with a strong, non-empty secret value. When the secret is non-empty, an attacker cannot forge valid signatures without knowing the secret.
CVE-2026-26078
This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). 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).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(low)
- EG Risk
- 38(Track)EG Risk 38/100SSVC: 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 computedSeverity75% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 13%
- KEV
- Not listed
Published
February 26, 2026
Last Modified
June 17, 2026
References (1)
- security-advisories@githubhttps://github.com/discourse/discourse/security/advisories/GHSA-frx4-wg35-4r68
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 3× in last 7d / 3× 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.
- 2026-07-28 15:36 UTCEPSS rescore
- 2026-07-27 14:04 UTCEG score recompute
- 2026-07-27 13:55 UTCOSV refresh
Related CVEs(same CWE)
Same CWE
10 shownCWE-639
- CVE-2018-25270EG 9.8CRITICAL
- CVE-2017-20223EG 9.8CRITICAL
- CVE-2019-25487EG 9.8EPSS p94CRITICAL
- CVE-2019-25235EG 9.8CRITICAL
- CVE-2019-15310EG 9.8EPSS p94CRITICAL
- CVE-2019-15913EG 9.8CRITICAL
- CVE-2019-16340EG 9.8EPSS p97CRITICAL
- CVE-2019-13360EG 9.8EPSS p98CRITICAL
- CVE-2019-12866EG 9.8CRITICAL
- CVE-2019-9756EG 9.8CRITICAL
Frequently asked(5)
What is CVE-2026-26078?
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-26078
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