78 xiaozhi-esp32 MCP Response mcp_server.cc ParseMessage improper synchronization

published 2026-06-28 4 mo ago modified 2026-10-25 14 d ago also EUVD-2026-39989

cvss: 3.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 28%
public exploits: 0; none known

A weakness has been identified in 78 xiaozhi-esp32 up to 2.2.6. Affected by this issue is the function ParseMessage of the file main/mcp_server.cc of the component MCP Response Handler. This manipulation causes improper synchronization. Remote exploitation of the attack is possible. The attack's complexity is rated as high. The exploitation is known to be difficult. The exploit has been made available to the public and could be used for attacks. The pull request to fix this issue awaits acceptance.

Patch / fix

links 1

github.com/78/xiaozhi-esp32#2021 pull request

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 4 mo ago (2026-06-29)

Exploit prediction

0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/78/xiaozhi-esp32/issues/2020 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	2.3	CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
CNA	3.1	3.1	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	3.0	3.1	CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R
CNA	2.0	2.1	AV:N/AC:H/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:UR
CNA	4.0	1.3	CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	3.1	CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
CNA	2.0	2.1	AV:N/AC:H/Au:S/C:N/I:P/A:N

Affected products

78 xiaozhi-esp32

Classification

Weakness

CWE-662 Improper Synchronization

References

github.com /78/xiaozhi-esp32/pull/2021
issue-tracking, patch
github.com /78/xiaozhi-esp32/issues/2020
exploit, issue-tracking
vuldb.com /vuln/374486
vdb-entry, technical-description
vuldb.com /vuln/374486/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-13489
third-party-advisory
vuldb.com /submit/838198
third-party-advisory
github.com /78/xiaozhi-esp32/
product

Sources

CVE List CVE-2026-13489
NVD CVE-2026-13489

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary