CVE-2018-5241
Symantec Advanced Secure Gateway (ASG) 6.6 and 6.7, and ProxySG 6.5, 6.6, and 6.7 are susceptible to a SAML authentication bypass vulnerability.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (4.52%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Symantec Advanced Secure Gateway (ASG) 6.6 and 6.7, and ProxySG 6.5, 6.6, and 6.7 are susceptible to a SAML authentication bypass vulnerability. The products can be configured with a SAML authentication realm to authenticate network users in intercepted proxy traffic. When parsing SAML responses, ASG and ProxySG incorrectly handle XML nodes with comments. A remote attacker can modify a valid SAML response without invalidating its cryptographic signature. This may allow the attacker to bypass user authentication security controls in ASG and ProxySG. This vulnerability only affects authentication of network users in intercepted traffic. It does not affect administrator user authentication for the ASG and ProxySG management consoles.
- CVSS 3.0
- 9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 4.52% probability · 91th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Affected
- broadcom/advanced secure gateway · broadcom/symantec proxysg
- Source
- secure@symantec.com
EPSS 4.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/104282Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1040993Third Party Advisory, VDB Entry
- https://www.symantec.com/security-center/network-protection-security-advisories/SA167Vendor Advisory
- http://www.securityfocus.com/bid/104282Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1040993Third Party Advisory, VDB Entry
- https://www.symantec.com/security-center/network-protection-security-advisories/SA167Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.