SB2021091342 - SUSE update for apache2-mod_auth_openidc
Published: September 13, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 vulnerabilities.
1) Format string error (CVE-ID: CVE-2021-32785)
CWE-ID: CWE-134 - Use of Externally-Controlled Format String
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a format string error as mod_auth_openidc wrongly performs argument interpolation before passing Redis requests to `hiredis. A remote attacker can supply a specially crafted input that contains format string specifiers and perform a denial of service (DoS) attack.
2) Open redirect (CVE-ID: CVE-2021-32786)
CWE-ID: CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to redirect victims to arbitrary URL.
The vulnerability exists due to improper sanitization of user-supplied data in oidc_validate_redirect_url() function. A remote attacker can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.
Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.
3) Use of insufficiently random values (CVE-ID: CVE-2021-32791)
CWE-ID: CWE-330 - Use of Insufficiently Random Values
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to perform a brute-force attack.
The vulnerability exists due to the AES GCM encryption in mod_auth_openidc uses a static IV and AAD, which creates a static nonce. Since aes-gcm is a stream cipher, this can lead to known cryptographic issues as the same key is being reused.
4) Cross-site scripting (CVE-ID: CVE-2021-32792)
CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear
The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.
The vulnerability exists due to insufficient sanitization of user-supplied data within the "OIDCPreservePost On". A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.
Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.
Remediation
Install update from vendor's website.