Unpatched Remote Hacking Flaw Disclosed in Fortinet's FortiWeb WAF
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2018-13379 | Unauthenticated Path Traversal in Fortinet FortiOS SSL VPN CVE-2018-13379 is a path traversal flaw (CWE-22) in the Fortinet FortiOS SSL VPN web portal that allows an unauthenticated attacker to download FortiOS system files via specially crafted HTTP resource requests. By traversing directories through crafted requests to the exposed web portal, the attacker can retrieve sensitive files, a technique publicly documented as yielding the SSL VPN session file containing usernames and passwords in plaintext. Any organization running the SSL VPN web portal on a FortiGate appliance is affected, and risk is highest where the portal is directly reachable from the internet. The flaw is confirmed in the wild: it was added to the CISA KEV catalog on 2021-11-03 with known ransomware use, and EPSS assigns it a 100% probability of exploitation within 30 days. No public PoC is listed in the provided data, but credential theft tied to this bug has been widely reused by threat actors. Do: Apply the patched FortiOS release per Fortinet's vendor advisory immediately, as this is a CISA KEV required action; if the fixed version is not known from this data, follow Fortinet's FG-IR-18-384 advisory for the correct upgrade path. Rotate SSL VPN credentials and review VPN access logs for path-traversal requests, since successful exploitation exposes plaintext session credentials, and restrict SSL VPN portal exposure to trusted sources where possible. | 9.8 | 100% | KEV ransomware |
| mass≈500,000 internet-exposed FortiOS SSL VPN portals (Fortinet cited ~480,000 affected devices) | |
| CVE-2019-5591 | Default-Configuration LDAP Impersonation in Fortinet FortiOS CVE-2019-5591 is a default-configuration flaw in Fortinet FortiOS (CWE-306, missing authentication for a critical function): when a FortiGate acts as an LDAP client over SSL/TLS for authentication purposes, the default configuration does not properly authenticate the LDAP server, allowing an unauthenticated attacker on the same subnet to impersonate the LDAP server. The attack requires adjacency (the attacker must be on the same network segment as the device's LDAP traffic) and only works where the device uses LDAP over TLS with the default, non-validating settings. A successful attacker can intercept sensitive authentication information, such as usernames and passwords, exchanged with the LDAP server, with high confidentiality impact but no integrity or availability impact per the CVSS score. Organizations running affected FortiOS releases with LDAP-over-TLS configured are exposed; FortiOS runs on one of the largest firewall/VPN installed bases, though the source data does not state exact affected version ranges or deployment counts. The flaw is listed in CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03) with known in-the-wild and ransomware use; late-2021 CISA and FBI advisories warned that APT actors were exploiting Fortinet bugs, including this one, for initial access, and no public PoC is known. Do: Upgrade affected FortiGate/FortiOS units to a fixed release (6.2.1+, 6.0.8+, 5.6.10+, or 5.4.12+) per Fortinet's instructions, as required by CISA's KEV listing. If patching is delayed, disable the use of SSL/TLS in the LDAP server configuration or restrict and monitor the network path between the FortiGate and the LDAP server. Inventory which devices use LDAPS for authentication and review authentication logs for signs of server impersonation or credential theft. | 6.5 | 18% | KEV ransomware |
| largetens of thousands of FortiGate deployments plausibly affected (a subset of a very large FortiOS installed base that connects to LDAP over TLS) | |
| CVE-2020-12812 | MFA Bypass via Username Case Change in Fortinet FortiOS SSL VPN Fortinet FortiOS SSL VPN improperly validates the second factor of authentication (FortiToken), allowing a user with valid primary credentials to log in without being prompted for their one-time token. The bypass is triggered by changing the letter case of the username (e.g., typing 'Admin' instead of 'admin'), a case-sensitivity handling flaw (CWE-178) in the authentication logic (CWE-287). An attacker who has stolen, phished, or reused a user's primary credentials can therefore gain full SSL VPN access without the multi-factor protection defenders assume is enforced. Any organization running an affected FortiOS SSL VPN portal with FortiToken two-factor authentication for users is exposed. The flaw is in CISA's Known Exploited Vulnerabilities catalog (added 2021-11-03) with known ransomware use, and EPSS assigns a 49.3% probability of exploitation within 30 days (99th percentile); no public PoC is known. Do: Apply the FortiOS update per Fortinet's advisory, as required by CISA's KEV listing. Until patched, audit SSL VPN logs for successful logins in which no FortiToken second-factor prompt occurred (especially sessions authenticating with altered username case), and consider restricting the SSL VPN portal to trusted source addresses or disabling it temporarily. Any accounts found with second-factor-free VPN logins should have credentials rotated and be checked for follow-on compromise, given known ransomware use. | 9.8 | 49% | KEV ransomware |
| masson the order of hundreds of thousands of internet-exposed FortiOS SSL VPN portals (public scans in 2020-2021 counted roughly 150,000-500,000) | |
| CVE-2020-29015 | A blind SQL injection in the user interface of FortiWeb 6.3.0 through 6.3.7 and version before 6.2.4 may allow an unauthenticated, remote attacker to execute ar A blind SQL injection in the user interface of FortiWeb 6.3.0 through 6.3.7 and version before 6.2.4 may allow an unauthenticated, remote attacker to execute arbitrary SQL queries or commands by sending a request with a crafted Authorization header containing a malicious SQL statement. NVD description · AI analysis pending | 9.8 | 3% |
| — | ||
| CVE-2021-22123 | An OS command injection vulnerability in FortiWeb's management interface 6.3.7 and below, 6.2.3 and below, 6.1.x, 6.0.x, 5.9.x may allow a remote authenticated An OS command injection vulnerability in FortiWeb's management interface 6.3.7 and below, 6.2.3 and below, 6.1.x, 6.0.x, 5.9.x may allow a remote authenticated attacker to execute arbitrary commands on the system via the SAML server configuration page. NVD description · AI analysis pending | 8.8 | 77% |
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Full article569 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananAug 18, 2021
Details have emerged about a new unpatched security vulnerability in Fortinet's web application firewall (WAF) appliances that could be abused by a remote, authenticated attacker to execute malicious commands on the system.
"An OS command injection vulnerability in FortiWeb's management interface (version 6.3.11 and prior) can allow a remote, authenticated attacker to execute arbitrary commands on the system, via the SAML server configuration page," cybersecurity firm Rapid7 said in an advisory published Tuesday. "This vulnerability appears to be related to CVE-2021-22123, which was addressed in FG-IR-20-120."
Rapid7 said it discovered and reported the issue in June 2021. Fortinet is expected to release a patch at the end of August with version Fortiweb 6.4.1.
The command injection flaw is yet to be assigned a CVE identifier, but it has a severity rating of 8.7 on the CVSS scoring system. Successful exploitation of the vulnerability can allow authenticated attackers to execute arbitrary commands as the root user on the underlying system via the SAML server configuration page.
"An attacker can leverage this vulnerability to take complete control of the affected device, with the highest possible privileges," Rapid7's Tod Beardsley said. "They might install a persistent shell, crypto mining software, or other malicious software. In the unlikely event the management interface is exposed to the internet, they could use the compromised platform to reach into the affected network beyond the DMZ."
Rapid7 also warns that while authentication is a prerequisite for achieving arbitrary command execution, the exploit could be chained with an authentication bypass flaw, such as CVE-2020-29015. In the interim, users are advised to block access to the FortiWeb device's management interface from untrusted networks, including taking steps to prevent direct exposure to the internet.
Although there is no evidence that the new security issue has been exploited in the wild, it's worth noting that unpatched Fortinet servers have been a lucrative target for financially motivated and state-sponsored threat actors alike.
Earlier this April, the Federal Bureau of Investigation (FBI) and the Cybersecurity and Infrastructure Security Agency (CISA) warned of advanced persistent threat groups targeting Fortinet FortiOS servers by leveraging CVE-2018-13379, CVE-2020-12812, and CVE-2019-5591 to compromise systems belonging to government and commercial entities.
In the same month, Russian cybersecurity company Kaspersky revealed that threat actors exploited the CVE-2018-13379 vulnerability in FortiGate VPN servers to gain access to enterprise networks in European countries to deploy the Cring ransomware.
Update: Fortinet shared the following statement with The Hacker News:
“The security of our customers is always our first priority. Fortinet recognizes the important role of independent security researchers who work closely with vendors to protect the cybersecurity ecosystem in alignment with their responsible disclosure policies. In addition to directly communicating with researchers, our disclosure policy is clearly outlined on the Fortinet PSIRT Policy page, which includes asking incident submitters to maintain strict confidentiality until complete resolutions are available for customers. As such, we had expected that Rapid7 hold any findings prior to the end of our 90-day Responsible disclosure window. We regret that in this instance, individual research was fully disclosed without adequate notification prior to the 90-day window. We are working to deliver immediate notification of a workaround to customers and a patch released by the end of the week.”
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2021/08/unpatched-remote-hacking-zero-day-flaw.html