CVE-2023-42789Network attack vector

Code execution via captive-portal out-of-bounds write

Published Mar 12, 2024 · Updated Jul 8, 2026

Out-of-bounds write in FortiOS, FortiProxy, FortiPAM, and FortiSASE portals allows remote attackers to execute code via crafted HTTP requests. The captive-portal component writes request-derived data outside an intended buffer; Fortinet has not disclosed the exact request field or code path. Exploitation requires unauthenticated inside access to the captive portal and grants code or command execution on the affected service.

CVSS severity9.8
Critical
EPSS probability3.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in FortiOS, FortiProxy, FortiPAM, and FortiSASE portals allows remote attackers to execute code via crafted HTTP requests. The captive-portal component writes request-derived data outside an intended buffer; Fortinet has not disclosed the exact request field or code path. Exploitation requires unauthenticated inside access to the captive portal and grants code or command execution on the affected service.

The record

CVE
CVE-2023-42789
Published
Mar 12, 2024
Updated
Jul 8, 2026
Vendor
Fortinet
Product
FortiSASE
Classifications
CWE-787, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2024CVE publishedPublication date reported by the CVE source.
  2. Jul 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=23.2.b

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Fortinet · FortiSASEversion=23.2.b
Fortinet · FortiOSversion=6.2.0 <=6.2.15; version=6.4.0 <=6.4.14; version=7.0.0 <=7.0.12; version=7.2.0 <=7.2.5; version=7.4.0 <=7.4.1
Fortinet · FortiPAMversion=1.0.0 <=1.0.3; version=1.1.0 <=1.1.2
Fortinet · FortiProxyversion=2.0.0 <=2.0.13; version=7.0.0 <=7.0.12; version=7.2.0 <=7.2.6; version=7.4.0

Published CVSS scores

9.3FortinetCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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