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CVE-2001-1496: Acme Thttpd: Buffer overflow

CVE-2001-1496 is rated critical with a CVSS v3.1 base score of 9.8 and affects Acme Thttpd. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Off-by-one buffer overflow in Basic Authentication in Acme Labs thttpd 1.95 through 2.20 allows remote attackers to cause a denial of service and possibly execute arbitrary code.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-193: Off-by-one Error

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

Affected products

• Acme Thttpd: from 1.95 up to and including 2.20

References

• http://www.securityfocus.com/archive/1/241310
• http://www.securityfocus.com/archive/1/241953
• http://www.securityfocus.com/bid/3562
• https://exchange.xforce.ibmcloud.com/vulnerabilities/7595