Authentication Bypass in Palo Alto Networks PAN-OS Software
CVE-2026-0257

7.8HIGH

Key Information:

Vendor

Palo Alto Networks
Status
Cloud Ngfw
Pan-os
Prisma Access
Vendor
CVE Published:
13 May 2026

Badges

🔥 Trending now📈 Trended📈 Score: 7,670💰 Ransomware👾 Exploit Exists🟡 Public PoC🟣 EPSS 36%🦅 CISA Reported📰 News Worthy

What is CVE-2026-0257?

CVE-2026-0257 is a significant vulnerability found in Palo Alto Networks' PAN-OS software, specifically affecting the GlobalProtect portal and gateway. This vulnerability facilitates an authentication bypass, allowing unauthorized users to establish a VPN connection without proper security credentials. The PAN-OS software is essential for managing network security and facilitating secure remote access for organizations. The exploitation of this vulnerability can lead to unauthorized access to sensitive internal networks, potentially exposing critical data and resources to malicious actors. By leveraging this flaw, attackers can bypass essential security mechanisms, undermining the overall integrity of the organizational security posture.

Potential impact of CVE-2026-0257

  1. Unauthorized Network Access: Exploitation of this vulnerability enables attackers to gain unauthorized access to internal network resources, posing a severe risk to data confidentiality, integrity, and availability.

  2. Data Breaches: Organizations face the threat of significant data breaches, as attackers can potentially access sensitive information, including personally identifiable information (PII), financial data, and proprietary assets.

  3. Increased Security Risks: The ability to bypass established security protocols can lead to further vulnerabilities, as attackers may use this access to deploy additional malicious activities, including data exfiltration, deploying ransomware, or infiltrating deeper into the network.

CISA has reported CVE-2026-0257

CISA provides regional cyber and physical services to support security and resilience across the United States. CISA monitor the most dangerious vulnerabilities and have identifed CVE-2026-0257 as being exploited but is not known by the CISA to be used in ransomware campaigns. This is subject to change at pace as recent news articles suggest the vulnerability is being used by ransomware groups.

The CISA's recommendation is: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Affected Version(s)

PAN-OS 12.1.0 < 12.1.7, 12.1.4-h6

PAN-OS 11.2.0 < 11.2.12, 11.2.10-h7, 11.2.7-h14, 11.2.4-h17

PAN-OS 11.1.0 < 11.1.15, 11.1.13-h5, 11.1.10-h25, 11.1.7-h6, 11.1.6-h32, 11.1.4-h33

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-0257
Created by sfewer-r7

CVE-2026-0257
Created by Mr-Robot-LP

CVE-2026-0257
Created by HORKimhab

News Articles

favicon imageDark Reading

Patch Now: Palo Alto Auth Bypass Bug Under Active Exploit

Exploiting the PAN-OS GlobalProtect VPN vulnerability requires certain conditions, but adversaries have done so in two attack waves that started mid-May.

1 day ago

favicon imagetheregister

Palo Alto VPN bug graduates from advisory to active exploitation

Rapid7: Attackers exploit authentication bypass flaw in the wild, meaning more emergency patching for PAN-OS users

1 day ago

favicon imageIt Security News

Hackers are exploiting Palo Alto GlobalProtect VPN authentication bypass (CVE-2026-0257) - IT Security News

Authentication bypass vulnerabilities (CVE-2026-0257) in Palo Alto Networks’ firewalls that the company disclosed on May 13 have been targeted in “limited exploit attempts”. “Across multiple customers, Rapid7 observed successful exploitation via authentication probes using forged cookies, but the ap...

2 days ago

References

https://security.paloaltonetworks.com/CVE-2026-0257
vendor-advisory

EPSS Score

36% chance of being exploited in the next 30 days.

CVSS V4

Score:
7.8
Severity:
HIGH
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 💰

    Used in Ransomware

  • 📈

    Vulnerability started trending

  • 🟡

    Public PoC available

  • 🦅

    CISA Reported

  • 📰

    First article discovered by It Security News

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Palo Alto Networks thanks our internal security research teams for discovering and reporting this issue.
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