CVE-2021-42756

CRITICALCVSS 9.8/10EPSS 36.41%

Last modified

CVE-2021-42756 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.. EPSS estimates a 36.41% chance of exploitation in the next 30 days.

Description

Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.

Metrics

CVSS 3.1
9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
36.41%

98.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
FortinetFortiweb>= 5.6.0, < 6.0.8
FortinetFortiweb>= 6.1.0, < 6.1.3
FortinetFortiweb>= 6.2.0, < 6.2.7
FortinetFortiweb>= 6.3.0, < 6.3.17
FortinetFortiweb>= 6.4.0, <= 6.4.2

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2021-42756?
Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.
How severe is CVE-2021-42756?
CVE-2021-42756 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 36.41% probability of exploitation in the next 30 days.
How do I fix CVE-2021-42756?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-42756?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST