CVE-2021-42717

ModSecurity 3.x through 3.0.5 mishandles excessively nested JSON objects. Crafted JSON objects with nesting tens-of-thousands deep could result in the web server being unable to service legitimate requests. Even a moderately large (e.g., 300KB) HTTP request can occupy one of the limited NGINX worker processes for minutes and consume almost all of the available CPU on the machine. Modsecurity 2 is similarly vulnerable: the affected versions include 2.8.0 through 2.9.4.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
mitreCNA
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CVEADP
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Base Score
CVSS 3.x
EPSS Score
Percentile: 82%
VendorProductVersion
trustwavemodsecurity
2.0.0 ≤
𝑥
< 2.9.5
trustwavemodsecurity
3.0.0 ≤
𝑥
< 3.0.6
debiandebian_linux
9.0
debiandebian_linux
10.0
debiandebian_linux
11.0
oraclehttp_server
12.2.1.3.0
oraclehttp_server
12.2.1.4.0
oraclezfs_storage_appliance_kit
8.8
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
modsecurity
bullseye
no-dsa
buster
no-dsa
bookworm
3.0.9-1+deb12u1
fixed
sid
3.0.13-1
fixed
trixie
3.0.13-1
fixed
modsecurity-apache
bullseye
2.9.3-3+deb11u2
no-dsa
buster
no-dsa
bullseye (security)
2.9.3-3+deb11u1
fixed
bookworm
2.9.7-1
fixed
sid
2.9.8-1
fixed
trixie
2.9.8-1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
modsecurity
noble
needs-triage
mantic
ignored
lunar
ignored
kinetic
ignored
jammy
needs-triage
impish
ignored
hirsute
ignored
focal
needs-triage
xenial
ignored
trusty
ignored
modsecurity-apache
noble
not-affected
mantic
not-affected
lunar
not-affected
kinetic
ignored
jammy
not-affected
impish
ignored
hirsute
ignored
focal
Fixed 2.9.3-1ubuntu0.1
released
bionic
Fixed 2.9.2-1ubuntu0.1~esm1
released
xenial
Fixed 2.9.0-1ubuntu0.1~esm1
released
trusty
not-affected