CVE-2026-4903: tenda ac5_firmware
Vulnerability summary
CVE-2026-4903 is a high (CVSS 9.0) vulnerability in tenda ac5_firmware. EPSS estimates a 1.01% chance of exploitation in the next 30 days, higher than 62.6% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 26-03-2026PublishedVulnerability first disclosed.
- 27-03-2026Last modifiedVulnerability information updated.
Description
A flaw has been found in Tenda AC5 15.03.06.47. This vulnerability affects the function formQuickIndex of the file /goform/QuickIndex of the component POST Request Handler. This manipulation of the argument PPPOEPassword causes stack-based buffer overflow. The attack may be initiated remotely. The exploit has been published and may be used.
CVSS metrics
7 scores · 2 sources · 4 versions- NVDNIST7.4HighCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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:XDiffers
- NVDNIST8.8HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.0HighAV:N/AC:L/Au:S/C:C/I:C/A:C
EPSS trend
Probability
1.01%
Chance of exploitation in the next 30 days
Percentile
63%
Versus all other CVEs
30-day change
-4.45 pp
From 5.46% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (lavender-bicycle-a5a.notion.site)
Maturity: unknown
Weaknesses
CWE · root cause- CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
- 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
Tenda1 product
- ac5_firmware15.03.06.47
1 vendor · 1 product
References
5 links- lavender-bicycle-a5a.notion.site/Tenda_AC5_QuickIndex_PPPOEPassword-32053a41781f808dae98f99c99bcb21cExploitThird Party Advisory
- www.tenda.com.cnProduct