CVE-2026-51263

✕ Withdrawn — historical dataCRITICALPre-NVD 9.8Elevated
9.8CVSS
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%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
EchelonGraph score
Not yet assessedThis CVE record was withdrawn by its numbering authority, so there is no vulnerability to rate.
EG Score
—
EG Risk
—
EPSS PROB
0%
EPSS %ILE
36%
KEV
Not listed

Published

July 28, 2026

Last Modified

July 28, 2026

Advisory Details (2)

Auto-updated Sep 9, 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 2× in last 7d / 9× 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. 2026-09-13 07:55 UTCGHSA enrichment
  2. 2026-09-10 14:34 UTCGHSA enrichment
  3. 2026-09-07 20:57 UTCGHSA enrichment
  4. 2026-09-04 12:09 UTCGHSA enrichment
  5. 2026-08-30 17:23 UTCGHSA enrichment
  6. 2026-08-28 00:01 UTCGHSA enrichment
  7. 2026-08-25 06:39 UTCGHSA enrichment
  8. 2026-08-22 13:10 UTCGHSA enrichment
  9. 2026-08-19 19:48 UTCGHSA enrichment
  10. 2026-08-17 00:36 UTCGHSA enrichment
  11. 2026-08-14 07:14 UTCGHSA enrichment
  12. 2026-08-11 13:53 UTCGHSA enrichment
  13. 2026-08-08 20:32 UTCGHSA enrichment
  14. 2026-08-06 03:10 UTCGHSA enrichment
  15. 2026-08-03 09:49 UTCGHSA enrichment
  16. 2026-08-01 04:16 UTCEPSS rescore
  17. 2026-07-31 16:27 UTCEG score recompute▼ 9.80
  18. 2026-07-31 16:27 UTCGHSA enrichment
  19. 2026-07-31 12:06 UTCGHSA enrichment
  20. 2026-07-31 07:48 UTCGHSA enrichment
  21. 2026-07-31 03:30 UTCGHSA enrichment
  22. 2026-07-30 23:14 UTCGHSA enrichment
  23. 2026-07-30 18:57 UTCEG score recompute
  24. 2026-07-30 18:57 UTCGHSA enrichment
  25. 2026-07-30 16:28 UTCEPSS rescore
Show 21 more
  1. 2026-07-30 14:40 UTCGHSA enrichment
  2. 2026-07-30 10:12 UTCEG score recompute
  3. 2026-07-30 10:12 UTCGHSA enrichment
  4. 2026-07-30 05:55 UTCGHSA enrichment
  5. 2026-07-30 01:38 UTCEG score recompute
  6. 2026-07-30 01:38 UTCGHSA enrichment
  7. 2026-07-30 01:30 UTCEPSS rescore
  8. 2026-07-29 21:11 UTCGHSA enrichment
  9. 2026-07-29 16:52 UTCGHSA enrichment
  10. 2026-07-29 12:35 UTCGHSA enrichment
  11. 2026-07-29 08:18 UTCGHSA enrichment
  12. 2026-07-29 04:01 UTCGHSA enrichment
  13. 2026-07-28 23:45 UTCEG score recompute
  14. 2026-07-28 23:44 UTCGHSA enrichment
  15. 2026-07-28 19:27 UTCEG score recompute
  16. 2026-07-28 19:27 UTCGHSA enrichment
  17. 2026-07-28 18:24 UTCEG score recompute▲ 9.80
  18. 2026-07-28 18:22 UTCMITRE cvelistV5CVSS v3 → 9.8 · severity → CRITICAL
  19. 2026-07-28 16:19 UTCNVD update
  20. 2026-07-28 15:30 UTCEG score recompute
  21. 2026-07-28 15:29 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

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.
Is CVE-2026-51263 actively exploited?
CVE-2026-51263 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 64.3% of all scored CVEs.
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

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