Cyber Resilience

CVE-2023-23781

Memory Safety in Fortinet Fortiweb 6.3.0 – 6.3.20

Memory Safety
Published
16 February 2023
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 6.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0070 50th percentile
Risk Priority 50 floored blend · peak EPSS

Summary

CVE-2023-23781 is a medium-severity Stack-based Buffer Overflow (CWE-121) vulnerability in Fortinet Fortiweb. Its CVSS base score is 6.4 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 50th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

A stack-based buffer overflow vulnerability [CWE-121] in FortiWeb version 7.0.1 and below, 6.4 all versions, version 6.3.19 and below SAML server configuration may allow an authenticated attacker to achieve arbitrary code execution via specifically crafted XML files.

CWE(s)
CWE-121CWE-787

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-25602Same product: Fortinet Fortiweb
CVE-2023-23780Same product: Fortinet Fortiweb
CVE-2026-24640Same product: Fortinet Fortiweb
CVE-2023-23782Same product: Fortinet Fortiweb
CVE-2024-21758Same product: Fortinet Fortiweb
CVE-2025-32766Same product: Fortinet Fortiweb
CVE-2026-30897Same product: Fortinet Fortiweb
CVE-2023-33308Same vendor: Fortinet
CVE-2023-29182Same vendor: Fortinet
CVE-2023-46720Same vendor: Fortinet

Affected Assets

fortinet
fortiweb
6.3.0 — 6.3.20 · 6.4.0 — 6.4.2 · 7.0.0 — 7.0.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

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Detect
Catch it (NIST detect / respond)

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Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)

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Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure-development practices directly prevent introduction of stack buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability scanning can discover stack buffer overflows but does not prevent their introduction.

PR.PS-02 partial match
prevents

Patching eliminates known instances of the weakness after discovery.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing (fuzzing, static analysis) detects stack overflows before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates buffer-safety practices that directly prevent stack overflows.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify buffer-size and input-validation rules.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles include memory-safety and least-privilege stack usage.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe buffer handling that causes CWE-121.

A.8.32 Change management partial match
prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. prevents CWE-121
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-121

References