CVE-2026-82273

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-28. a secondary CVSS source baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
Trending — 4 sources updated this weekElevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Mastra through 1.63.0 contains an authentication bypass vulnerability in the memory API thread ownership validation when mapUserToResourceId callback is omitted from configuration. Authenticated attackers can enumerate all threads via GET /api/memory/threads and read conversation history and metadata of other resource owners.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
45(Track)
EG Risk 45/100SSVC: 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 computed
Severity65% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
23%
KEV
Not listed

Published

August 28, 2026

Last Modified

August 28, 2026

Advisory Details (4)

Auto-updated Aug 28, 2026
No patch confirmed yet.
generic

Mastra Memory API Thread Ownership Check Is a No-op When mapUserToResourceId Is Unset | Advisories | VulnCheck

https://www.vulncheck.com/advisories/mastra-memory-api-thread-ownership-check-is-a-no-op-when-mapusertoresourceid-is-unset
generic

mastra/packages/server/src/server/handlers/utils.ts at b7e66f0c478a227985e0062794ef058c3714fabf · mastra-ai/mastra · GitHub

https://github.com/mastra-ai/mastra/blob/b7e66f0c478a227985e0062794ef058c3714fabf/packages/server/src/server/handlers/utils.ts
generic

GitHub - mastra-ai/mastra: Mastra is the modern TypeScript framework for AI-powered applications and agents. · GitHub

https://github.com/mastra-ai/mastra
generic

Memory API Cross-Resource Thread Enumeration (Missing Ownership Enforcement When mapUserToResourceId Is Not Configured) · Issue #18911 · mastra-ai/mastra · GitHub

https://github.com/mastra-ai/mastra/issues/18911

Vendor Advisories for CVE-2026-82273(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 7× 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.

  1. 2026-08-30 01:22 UTCEPSS rescore
  2. 2026-08-29 20:41 UTCGHSA enrichment
  3. 2026-08-28 22:48 UTCEG score recompute
  4. 2026-08-28 22:48 UTCGHSA enrichment
  5. 2026-08-28 20:26 UTCEG score recompute
  6. 2026-08-28 19:40 UTCEG score recompute
  7. 2026-08-28 19:36 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-82273?
CVE-2026-82273 is a medium vulnerability published on August 28, 2026. Mastra through 1.63.0 contains an authentication bypass vulnerability in the memory API thread ownership validation when mapUserToResourceId callback is omitted from configuration. Authenticated attackers can enumerate all threads via GET /api/memory/threads and read conversation history and…
When was CVE-2026-82273 disclosed?
CVE-2026-82273 was first published in the National Vulnerability Database on August 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-82273 actively exploited?
CVE-2026-82273 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 77.4% of all scored CVEs.
What is the CVSS score of CVE-2026-82273?
CVE-2026-82273 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-82273?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-82273, 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-2026-82273

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