FAST FAC1200R MmtAtePrase stack-based overflow

published 2026-09-28 42 d ago modified 2026-09-28 41 d ago also EUVD-2026-88207

cvss: 9.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 38%
public exploits: 0; none known

A vulnerability was determined in FAST FAC1200R 5.0_20201119_1.0.2. Affected by this vulnerability is the function MmtAtePrase of the component MmtAtePrase Parser. This manipulation causes stack-based buffer overflow. Remote exploitation of the attack is possible. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure but did not respond in any way.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 42 d ago (2026-09-28)

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 38% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/xiaobor123/vuls-find-VxWorks/tree/main/vul-find-FAST_FAC1200R-twlantask-MmtAtePrase-stack-overflow(1)/vul-find-FAST_FAC1200R-twlantask-MmtAtePrase-stack-overflow referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.4	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P
CNA	3.1	9.9	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	3.0	9.9	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R
CNA	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR
CNA	4.0	8.6	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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
NVD	3.1	9.9	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CNA	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C

Affected products

FAST FAC1200R

Classification

Weakness

CWE-121 Stack-based Buffer Overflow
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

github.com /xiaobor123/vuls-find-VxWorks/tree/main/vul-find-FAST_FAC1200R-twlantask-MmtAtePrase-stack-overflow(1)/vul-fin
exploit
vuldb.com /vuln/410906
vdb-entry, technical-description
vuldb.com /vuln/410906/cti
signature, permissions-required
vuldb.com /cve/CVE-2026-101038
third-party-advisory
vuldb.com /submit/927237
third-party-advisory

Sources

CVE List CVE-2026-101038
NVD CVE-2026-101038

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