SSL: Null Byte in Common Name

This signature detects attempts to exploit a known vulnerability against multiple browsers. If a null-byte is present in the certificate name, the certificate displays incompletely, so an attacker could use a man-in-the-middle attack over the encrypted channel using this method.

Extended Description

GnuTLS is prone to a security-bypass vulnerability because it fails to properly validate the domain name in a signed CA certificate, allowing attackers to substitute malicious SSL certificates for trusted ones. Successfully exploiting this issue allows attackers to perform man-in-the-middle attacks or impersonate trusted servers, which will aid in further attacks. Versions prior to GnuTLS 2.8.2 are vulnerable.

Affected Products

Gnu gnutls

References

BugTraq: 35952

Short Name

SSL:INVALID:NULL-CERT

Severity

Minor

Recommended

False

Recommended Action

None

SSL: Null Byte in Common Name

Extended Description

Affected Products

References

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