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
02 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
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 34.97% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 98.2% of scored records. A rank, not a probability.
- NVD base score
- 9.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2023-02-16 18:05Z3 YR AGO
- Last updated
- 2024-10-23 14:49Z2 YR AGO
- Reserved
- 2021-10-20
- Assigning CNA
- fortinet
- Record state
- PUBLISHED
- Severity
- Critical (CVSS 9.3)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:C
- Weaknesses
- Data version
- 5.1
- Document digest
- 301885ab05f42a3a3c0d658f775c3eba5068711a25f82c577770e22e3bf0fb0e
05 Affected products
06 References
- fortiguard.comhttps://fortiguard.com/psirt/FG-IR-21-186
07 Remediation
Upgrade to FortiWeb 7.0.0 or above, Upgrade to FortiWeb 6.3.17 or above, Upgrade to FortiWeb 6.2.7 or above. Upgrade to FortiWeb 6.1.3 or above. Upgrade to FortiWeb 6.0.8 or above.