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Fencer Intel
high 7.5

CVE-2025-66263 json

Unauthenticated Arbitrary File Read via Null Byte Injection

published 11mo ago modified 21d ago also EUVD-2025-199670

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 36%
public exploits
0
none known

Summary

Unauthenticated Arbitrary File Read via Null Byte Injection in DB Electronica Telecomunicazioni S.p.A. Mozart FM Transmitter versions 30, 50, 100, 300, 500, 1000, 2000, 3000, 3500, 6000, 7000 allows an attacker to perform Null byte injection in download_setting.php allows reading arbitrary files. The `/var/tdf/download_setting.php` endpoint constructs file paths by concatenating user-controlled `$_GET['filename']` with a forced `.tgz` extension. Running on PHP 5.3.2 (pre-5.3.4), the application is vulnerable to null byte injection (%00), allowing attackers to bypass the extension restriction and traverse paths. By requesting `filename=../../../../etc/passwd%00`, the underlying C functions treat the null byte as a string terminator, ignoring the appended `.tgz` and enabling unauthenticated arbitrary file disclosure of any file readable by the web server user.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
11mo ago

Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • abdulmhsblog.com https://www.abdulmhsblog.com/posts/webfmvulns/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 8.9 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
CNA 4.0 8.9 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/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 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

  • DB Electronica Telecomunicazioni S.p.A. Mozart FM Transmitter

Classification

Weakness
  • CWE-158 Improper Neutralization of Null Byte or NUL Character

References

Sources

Fencer Intel 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.