HomeBox is a home inventory and organization system. Prior to 0.26.0, NotifierRepository.Update in backend/internal/data/repo/repo_notifier.go updates a notifier through UpdateOneID(id) without requiring the record's user ID to match the authenticated user. An authenticated user who supplies another tenant's notifier UUID to PUT /v1/notifiers/{id} can read the returned stored url, which may contain plaintext Shoutrrr credentials for Slack, SMTP, Telegram, Pushover, or Discord, and can replace the URL to redirect the victim's notifications to an attacker-controlled webhook. This issue is fixed in version 0.26.0.
CVE-2026-48976
HIGHPre-NVD 8.18.1—Trending — 3 sources updated this week
EchelonGraph scoreMEDIUM confidence
This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 64% 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).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.1Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 8.1(medium)
- EG Risk
- 37(Track)EG Risk 37/100SSVC: 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 computedSeverity81% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 36%
- KEV
- Not listed
Published
September 21, 2026
Last Modified
September 23, 2026
Advisory Details (3)
Auto-updated Sep 21, 2026Patch available. Sources: github, github_commit, github_release.
github_release Patch Available
v0.26.0
Patch available: sysadminsmedia/homebox v0.26.0
https://github.com/sysadminsmedia/homebox/releases/tag/v0.26.0github_commit
commit ed3216a80998 (sysadminsmedia/homebox)
Fix landed in sysadminsmedia/homebox commit ed3216a80998 — awaiting tagged release
https://github.com/sysadminsmedia/homebox/commit/ed3216a80998dfd81d4418700696244144883160github Patch Available
Cross-Tenant IDOR in Notifier Update Leaks Shoutrrr Credentials and Allows Webhook Hijack in Homebox · Advisory · sysadminsmedia/homebox · GitHub
https://github.com/sysadminsmedia/homebox/security/advisories/GHSA-mc8h-5c5v-37p7Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× 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.
- 2026-09-24 19:32 UTCEG score recompute
- 2026-09-23 18:39 UTCEG score recompute
- 2026-09-23 17:53 UTCEPSS rescore
- 2026-09-22 19:20 UTCEG score recompute
- 2026-09-21 18:27 UTCEG score recompute
- 2026-09-21 18:00 UTCEG score recompute
- 2026-09-21 17:45 UTCEG score recompute
- 2026-09-21 17:45 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-48976?
CVE-2026-48976 is a high vulnerability published on September 21, 2026. HomeBox is a home inventory and organization system. Prior to 0.26.0, NotifierRepository.Update in backend/internal/data/repo/repo_notifier.go updates a notifier through UpdateOneID(id) without requiring the record's user ID to match the authenticated user. An authenticated user who supplies…
When was CVE-2026-48976 disclosed?
CVE-2026-48976 was first published in the National Vulnerability Database on September 21, 2026, with the most recent update on September 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-48976 actively exploited?
CVE-2026-48976 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 63.7% of all scored CVEs.
What is the CVSS score of CVE-2026-48976?
CVE-2026-48976 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-48976?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-48976, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-48976
Is Your Infrastructure Affected by CVE-2026-48976?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.