ZeroHour

CVE-2026-20316

KEV ransomwarelarge

Hard-Coded Password Vulnerability in Cisco Secure Firewall Management Center

CISA: Cisco Secure Firewall Management Center Use of Hard-coded Password Vulnerability

CVSS 3.1
5.3 medium
EPSS
11%p96
Published
()
KEV added
AI analysis

Cisco Secure Firewall Management Center (FMC), formerly Firepower Management Center, contains a use of hard-coded password vulnerability (CWE-259) that allows an unauthenticated, remote attacker to log in to an affected system. By authenticating with the built-in hard-coded credentials for a low-privileged account, the attacker can gain access to sensitive data within the impacted systems. Any organization running an affected Cisco FMC deployment is exposed, particularly where the management interface is reachable from untrusted networks. The flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2026-07-29, indicating active exploitation in the wild, and related reporting describes active exploitation of FMC vulnerabilities. No CVSS score or public proof-of-concept is yet available, but EPSS assigns a 9.8% probability of exploitation within 30 days (95th percentile).

What to do: Upgrade FMC to the fixed release per Cisco's security advisory, as no specific fixed version is provided in this data. Until patched, restrict access to the FMC management interface, audit recent logins against the affected low-privileged accounts, and rotate or remove any hard-coded credentials. Federal agencies must apply mitigations per CISA BOD 26-04 given the KEV listing dated 2026-07-29.

Affected
Cisco Secure Firewall Management Center (FMC)
Estimated exposure
largeplausibly tens of thousands of FMC deployments worldwide (no published install base) — FMC is the standard management console for Cisco's Secure Firewall/Firepower line, one of the most widely deployed enterprise firewall platforms, so installations plausibly number in the tens of thousands, with a subset of management…

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to log in to an affected device using a low-privileged account to access sensitive data within the impacted systems. This vulnerability is due to the presence of static user credentials for a low-privileged account. An attacker could exploit this vulnerability by using the account to log in to an affected system. A successful exploit could allow the attacker to log in to the affected system and access sensitive data as the low-privileged user. Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced. Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates. The reason is that this vulnerability can be used with other Cisco Secure FMC Software vulnerabilities to elevate privileges.

CISA Known Exploited Vulnerability
Affected
Cisco Secure Firewall Management Center (FMC)
Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Due date
Ransomware use
Known
Vendors
cisco
Products
secure firewall management center
Weakness
CWE-259
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

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Attackers Exploit Critical Cisco FMC Flaw to deploy Qilin ransomware

Three threat groups, including Qilin ransomware operators, exploit critical Cisco FMC flaws CVE-2026-20079 and CVE-2026-20316 for root access, credential theft, and ransomware.

Cisco Talos identified three post-compromise clusters exploiting recently patched Cisco Secure Firewall Management Center flaws. UAT-12197 deploys JSP web shells and harvests credentials; UAT-11823 (with Sandworm-overlapping tooling) installs Cyclops Blink for persistence; UAT-11988 (Qilin) uses static credentials, extensive reconnaissance, SOCKS5 proxies, reverse-SSH tunnels, AV killers, and ransomware deployment. CISA added CVE-2026-20079 to the KEV catalog with a September 12, 2026 patch deadline for federal agencies; Cisco urges immediate hotfix application.

Security Affairs · 4d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-203165· 2 reads

Active exploitation of Cisco Secure Firewall Management Center vulnerabilities

Cisco Talos reports in-the-wild exploitation of critical FMC flaw CVE-2026-20079 by three clusters including a Sandworm-linked APT and Qilin ransomware affiliates.

Cisco Talos is tracking active exploitation of CVE-2026-20079 (CVSS 10.0), an authentication bypass in Cisco Secure Firewall Management Center that lets unauthenticated remote attackers execute scripts and obtain root access, and CVE-2026-20316 (CVSS 5.3), which permits low-privileged logins and can be chained for privilege escalation. Talos identified three post-compromise clusters: UAT-12197 deploying JSP web shells and a JAR command executor for credential theft; UAT-11823, an APT overlapping with Sandworm, deploying a Netcat reverse shell and Cyclops Blink malware; and UAT-11988, assessed as a ransomware operator with TTPs consistent with Qilin affiliates. Hotfixes are available, with a comprehensive hardening release due the week of September 14, 2026.

Cisco Talos · 6d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Cisco FMC bugs exploited by nation-state and ransomware actors (CVE-2026-20079, CVE-2026-20316)

Cisco Talos confirms nation-state (Sandworm) and ransomware (Qilin) actors actively exploit CVE-2026-20079 and CVE-2026-20316 in Secure Firewall Management Center.

CVE-2026-20079 is a critical unauthenticated authentication bypass in the FMC web interface allowing root-level script and command execution via crafted HTTP requests; CVE-2026-20316 stems from static hard-coded credentials enabling unauthenticated logins. Cisco Talos detailed three intrusion clusters: web shell and JAR deployment for credential theft, a Sandworm-attributed reverse shell and credential-harvesting implant, and a suspected Qilin ransomware operator chain. Cisco urges immediate hotfixes ahead of a comprehensive hardening release the week of September 16, or taking the FMC management interface offline.

Help Net Security · 5d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Organizations Warned of Cisco Secure FMC Exploitation

Cisco and CISA warn that critical FMC authentication bypass CVE-2026-20079 is actively exploited; CISA added it to the KEV catalog with a September 12 deadline.

Cisco and CISA flagged active exploitation of CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center allowing remote, unauthenticated attackers to run malicious scripts and gain root access via crafted HTTP requests. Cisco patched the flaw in early March and added IoCs in late July, but confirmed active exploitation in its September 9 advisory; CISA added it to the KEV catalog requiring federal remediation by September 12. Talos identified three activity clusters exploiting CVE-2026-20079 and CVE-2026-20316, including state-sponsored and financially motivated actors, and this is the third FMC vulnerability in KEV this year after CVE-2026-20316 and CVE-2026-20131.

Critical Cisco FMC Flaws Actively Exploited to Gain Root Access and Deploy Malware

Threat actors actively exploit Cisco FMC CVE-2026-20079 (CVSS 10.0) for root access, with clusters linked to Sandworm and Qilin ransomware.

Cisco Talos warns of active exploitation of CVE-2026-20079, a CVSS 10.0 authentication bypass in Cisco Secure Firewall Management Center allowing unauthenticated root-level code execution, and CVE-2026-20316 (CVSS 5.3), which permits login via a low-privileged static account for privilege escalation. Hotfixes are available now, with a broader hardening release planned for the week of September 14. Three post-compromise activity clusters were identified: UAT-12197 deployed a home.jsp web shell and cmd.jar command executor; UAT-11823, attributed with high confidence to a Sandworm-linked APT, deployed a Netcat reverse shell and Cyclops Blink; and UAT-11988 showed Qilin ransomware tactics including Active Directory enumeration and credential theft before deploying Qilin ransomware.

GBHackers · 4d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Cisco confirms CVE-2026-20079 Secure FMC flaw exploited in attacks

Cisco confirmed active exploitation of CVE-2026-20079, a CVSS 10.0 authentication bypass enabling unauthenticated root command execution in Secure FMC; CISA added it to KEV.

Cisco confirmed in August 2026 that CVE-2026-20079 (CVSS 10.0), an unauthenticated authentication bypass in Secure Firewall Management Center, is being actively exploited, allowing remote attackers to execute scripts and commands as root via crafted HTTP requests to the web interface. CISA added the flaw to its Known Exploited Vulnerabilities catalog, ordering federal civilian agencies to patch by September 12, 2026. Shared IOCs, identical hot fixes, and a July 23 log entry suggest CVE-2026-20079 was used alongside the separately exploited static-credential flaw CVE-2026-20316 in the same attacks. Cisco released patches and cloud fixes, warns hot fixes do not remediate already-compromised devices, and says there are no workarounds.

BleepingComputer · 5d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Cisco FMC Flaws Exploited to Steal Credentials and Deploy Qilin Ransomware

Three threat clusters including a Sandworm-linked group and Qilin ransomware operators exploit Cisco FMC flaws CVE-2026-20079 and CVE-2026-20316.

Cisco Talos identified three clusters of post-compromise activity exploiting CVE-2026-20079 (CVSS 10.0, unauthenticated web-interface authentication bypass enabling root code execution) and CVE-2026-20316 (CVSS 5.3, low-privilege login exposing sensitive data) in Secure Firewall Management Center. UAT-12197 deployed JSP web shells and a JAR-based command executor to query internal databases for credentials; UAT-11823 used a Netcat reverse shell, configuration-harvesting scripts and a Cyclops Blink variant previously attributed to Russia's Sandworm; UAT-11988 used living-off-the-land FMC tooling for reconnaissance before deploying Qilin ransomware. CISA added CVE-2026-20079 to its KEV catalog, requiring FCEB agencies to patch by September 12, 2026; CVE-2026-20316 was added in late July 2026.

The Hacker News · 4d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Cisco FMC flaws exploited by ransomware gang, state-sponsored hackers

Cisco Talos confirms ransomware and state-sponsored groups exploited CVE-2026-20079 and CVE-2026-20316 in Secure Firewall Management Center, deploying Qilin ransomware and Cyclops Blink.

Cisco Talos identified three threat clusters (UAT-12197, UAT-11823, UAT-11988) exploiting CVE-2026-20079, a CVSS 10.0 authentication bypass, and CVE-2026-20316, a CVSS 5.3 static-credential flaw, in Cisco Secure Firewall Management Center. Qilin affiliates used static credentials for reconnaissance and deployed Qilin ransomware; a Sandworm-linked cluster deployed a Cyclops Blink backdoor via a malicious license.tmp file; a third cluster stole credentials through a JSP web shell. Cisco has released hotfixes and urges immediate installation, with broader patches expected next week.

BleepingComputer · 5d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Hackers Exploit Critical Cisco Firewall Flaw to Gain Root Access and Deploy Malware

State-sponsored and ransomware actors actively exploit critical Cisco FMC flaws CVE-2026-20079 (CVSS 10.0) and CVE-2026-20316 to gain root access and deploy ransomware.

Cisco Talos confirmed in-the-wild exploitation of CVE-2026-20079 (CVSS 10.0, unauthenticated authentication bypass enabling root command execution) and CVE-2026-20316 (CVSS 5.3, hard-coded static credentials) in Cisco Secure Firewall Management Center. Three activity clusters were identified: UAT-12197 dropping a JSP web shell and credential harvester; UAT-11823, assessed as Sandworm, deploying a Cyclops Blink variant; and UAT-11988, a Qilin ransomware affiliate chaining the flaws before deploying ransomware. CISA added both CVEs to the KEV catalog with a September 12 remediation deadline for federal agencies.

Cyber Security News · 5d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316

Sandworm-Linked Cyclops Blink Returns With Network Scanning and Packet-Sniffing Capabilities

Sophos uncovers a 64-bit Cyclops Blink variant on hacked Cisco FMC appliances, adding internal network scanning and selective packet capture; linked to Sandworm.

Sophos CTU analyzed a new 64-bit x86-64 Cyclops Blink implant (timezone_check) deployed on Cisco Secure Firewall Management Center appliances compromised via CVE-2026-20079 authentication bypass and CVE-2026-20316 low-privileged login. The activity is assessed with high confidence as Russian-nexus, with a moderate-confidence link to Sandworm (IRON VIKING, also tracked as Seashell Blizzard). The implant runs a parent controller plus five worker modules, masquerades as [kworker/0:1], persists via SysV init scripts at /lib/tz/timezone_check, and beacons to hard-coded C2 89.34.96.56 over a custom TLS protocol on ports 43856 and 49172. New module 0x11 scans internal IPv4 networks for SSH, SMB, LDAP, VMware, HTTP/HTTPS and VPN services, while module 0x12 performs filtered packet capture that can expose cleartext credentials, cookies and tokens.

GBHackers · 1d agoMalware in the wildCVE-2026-20079CVE-2026-20316

Week in review: Linux rootkit deployed on F5 BIG-IP APM devices, Cisco FMC bugs exploited

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State-sponsored and financially-motivated attackers are actively exploiting CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center (FMC), alongside CVE-2026-20316. N-able issued an emergency hotfix for CVE-2026-86218, a critical pre-auth RCE in the N-central RMM platform exploited in the wild. CERT Polska disclosed six RouterOS vulnerabilities being chained to hijack internet-exposed MikroTik devices. Microsoft's September 2026 Patch Tuesday shipped a record patch count including two zero-days, while roughly 67,000 Trezor customers faced phishing after a shipping-partner breach and researchers privately disclosed a zero-click WeChat worm to Tencent.

Help Net Security · 2d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316CVE-2026-862182· 1 read

ZDI-26-533: Cisco Secure Firewall Management Center login.cgi Authentication Bypass Vulnerability

ZDI discloses CVE-2026-20316, a 9.8-rated unauthenticated authentication bypass in Cisco Secure Firewall Management Center login.cgi.

ZDI-26-533 describes an authentication bypass vulnerability in Cisco Secure Firewall Management Center's login.cgi that allows remote attackers to bypass authentication without any credentials. ZDI assigned a CVSS score of 9.8, and the flaw is tracked as CVE-2026-20316. As a central management plane for firewall infrastructure, compromise could enable broad policy changes.

ZDI Published Advisories · Aug 11, 2026VulnerabilityCVE-2026-20316