CVE-2026-51263

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-28. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, ghsa
Trending — 4 sources updated this weekElevated
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 9.8Exploit: Elevated riskExposed: 0

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

schreibfaul1 ESP32-audioI2S 3.4.5 is vulnerable to Buffer Overflow. The Audio::openai_speech function in the Audio library manually constructs JSON request bodies and HTTP request headers by directly concatenating externally controllable input and instructions strings without effective length restriction and boundary validation. An unauthenticated remote attacker can send oversized malicious string data to trigger a heap buffer overflow during string splicing, resulting in memory corruption.

CVSS v3
9.8
EG Score
9.8(high)
EG Risk
75(Attend)
EG Risk 75/100SSVC: Attend

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
Severity98% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
—
EPSS %ILE
—
KEV
Not listed

Published

July 28, 2026

Last Modified

July 28, 2026

Advisory Details (2)

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

cveadvisory-/CVE-2026-51263 at main · programmervuln/cveadvisory- · GitHub

https://github.com/programmervuln/cveadvisory-/blob/main/CVE-2026-51263
generic

ESP32-audioI2S/src/Audio.cpp at master · schreibfaul1/ESP32-audioI2S · GitHub

https://github.com/schreibfaul1/ESP32-audioI2S/blob/master/src/Audio.cpp

Vendor Advisories for CVE-2026-51263(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 12× in last 7d / 12× 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. 2026-07-29 12:35 UTCGHSA enrichment
  2. 2026-07-29 08:18 UTCGHSA enrichment
  3. 2026-07-29 04:01 UTCGHSA enrichment
  4. 2026-07-28 23:45 UTCEG score recompute
  5. 2026-07-28 23:44 UTCGHSA enrichment
  6. 2026-07-28 19:27 UTCEG score recompute
  7. 2026-07-28 19:27 UTCGHSA enrichment
  8. 2026-07-28 18:24 UTCEG score recompute▲ 9.80
  9. 2026-07-28 18:22 UTCMITRE cvelistV5CVSS v3 → 9.8 · severity → CRITICAL
  10. 2026-07-28 16:19 UTCNVD update
  11. 2026-07-28 15:30 UTCEG score recompute
  12. 2026-07-28 15:29 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(4)

What is CVE-2026-51263?
CVE-2026-51263 is a critical vulnerability published on July 28, 2026. schreibfaul1 ESP32-audioI2S 3.4.5 is vulnerable to Buffer Overflow. The Audio::openai_speech function in the Audio library manually constructs JSON request bodies and HTTP request headers by directly concatenating externally controllable input and instructions strings without effective length…
When was CVE-2026-51263 disclosed?
CVE-2026-51263 was first published in the National Vulnerability Database on July 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-51263?
CVE-2026-51263 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-51263?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-51263, 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-2026-51263

Explore →

Is Your Infrastructure Affected by CVE-2026-51263?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs