CVE-2021-32976: Moxa NPort IAW5000A-I/O Series Serial Device Server Stack-based Buffer Overflow
Modified
Published 01-04-2022Last modified 16-04-2025
Vulnerability summary
CVE-2021-32976 is a critical (CVSS 9.8) Stack-based Buffer Overflow vulnerability in moxa nport iaw5000a-i/o series firmware. EPSS estimates a 2.79% chance of exploitation in the next 30 days, higher than 86.3% of scored vulnerabilities.
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)EPSS score
2.79%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded
Timeline
- 01-04-2022PublishedVulnerability first disclosed.
- 16-04-2025Last modifiedVulnerability information updated.
Description
Five buffer overflows in the built-in web server in Moxa NPort IAW5000A-I/O series firmware version 2.2 or earlier may allow a remote attacker to initiate a denial-of-service attack and execute arbitrary code.
CVSS metrics
3 scores · 2 sources · 2 versionsCritical 9.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 2 agree
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
High 7.5Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:P/I:P/A:PSourcesSingle source
EPSS trend
Probability
2.79%
Chance of exploitation in the next 30 days
Percentile
86%
Versus all other CVEs
30-day change
No change 0.00 pp
From 2.79% on 22-09-2026
22-09-202622-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
Moxa5 products
- nport iaw5000a-i/o series firmware≥ unspecified, ≤ 2.2
- nport_iaw5150a-12i\/o_firmware≤ 2.2
- nport_iaw5150a-6i\/o_firmware≤ 2.2
- nport_iaw5250a-12i\/o_firmware≤ 2.2
- nport_iaw5250a-6i\/o_firmware≤ 2.2
1 vendor · 5 products
References
2 links- www.cisa.gov/uscert/ics/advisories/icsa-21-187-01X Refsource CONFIRMMitigationThird Party AdvisoryUS Government Resource