Symantec Advanced Secure Gateway/ProxySG 6.5/6.6/6.7 SAML 7pk security

Summaryinfo

A vulnerability marked as critical has been reported in Symantec Advanced Secure Gateway and ProxySG 6.5/6.6/6.7. This vulnerability affects unknown code of the component SAML. This manipulation causes 7pk security. This vulnerability is tracked as CVE-2018-5241. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as critical was found in Symantec Advanced Secure Gateway and ProxySG 6.5/6.6/6.7 (Firewall Software). Affected by this vulnerability is an unknown code of the component SAML. The manipulation with an unknown input leads to a 7pk security vulnerability. The CWE definition for the vulnerability is CWE-254. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The bug was discovered 05/25/2018. The weakness was disclosed 05/29/2018 (Website). The advisory is shared at symantec.com. This vulnerability is known as CVE-2018-5241 since 01/05/2018. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/17/2023). MITRE ATT&CK project uses the attack technique T1211 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 4 days. During that time the estimated underground price was around $5k-$25k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 104282†). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Firewall Software

Vendor

• Symantec

Name

• Advanced Secure Gateway
• ProxySG

Version

• 6.5
• 6.6
• 6.7

License

• commercial

Website

• Vendor: https://www.symantec.com/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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