CVE-2025-52221: tenda ac6_firmware Out-of-bounds Write
CVSS: 9.8v3.1CriticalAnalyzed
Published 08-04-2026Last modified 10-04-2026
Vulnerability summary
CVE-2025-52221 is a critical (CVSS 9.8) Out-of-bounds Write vulnerability in tenda ac6_firmware. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.7% of scored vulnerabilities. 1 public exploit is recorded.
CVSS score
9.8/10
010
Critical · v3.1 (NVD)EPSS score
0.39%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github
Timeline
- 08-04-2026PublishedVulnerability first disclosed.
- 10-04-2026Last modifiedVulnerability information updated.
Description
Tenda AC6 15.03.05.16_multi is vulnerable to Buffer Overflow in the formSetCfm function via the funcname, funcpara1, and funcpara2 parameters.
CVSS metrics
2 scores · 2 sources · 1 versionCritical 9.8Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSources2 sources · 7.5–9.8
- CVE.orgCNA7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
EPSS trend
Probability
0.39%
Chance of exploitation in the next 30 days
Percentile
32%
Versus all other CVEs
30-day change
0.00 pp
From 0.39% on 21-09-2026
21-09-202621-10-2026
EPSS score0.39%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundIotvuln
Maturity: poc
Weaknesses
CWE · root cause- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.
Affected systems
Tenda1 product
- ac6_firmware15.03.05.16_multi
1 vendor · 1 product
References
2 links- github.com/faqiadegege/IoTVuln/blob/main/tendaAc6_formSetCfm_funcname_overflow/detail.mdExploitThird Party Advisory
- github.com/xiaotea/iot-vulnerability-collection/blob/main/README.mdThird Party Advisory