Dan Kaminsky

Daniel Kaminsky (February 7, 1979 – April 23, 2021) was an American computer security researcher based in San Francisco, California, widely known for his work on Domain Name System (DNS) security and for his role in one of the most closely coordinated vulnerability disclosures in Internet history. He worked at various points for Cisco, Avaya, IOActive (as Director of Penetration Testing), and later co-founded the security company White Ops, which was later renamed Human Security, where he served as Chief Scientist.

The 2008 DNS Cache Poisoning Discovery

In early-to-mid 2008, while at IOActive, Kaminsky discovered a fundamental design flaw affecting the DNS protocol itself, not just a single implementation. Because DNS queries relied on a transaction ID field with only 65,536 possible values, an attacker could feasibly guess or brute-force the ID and inject forged responses into a resolver's cache, allowing traffic for a targeted domain to be redirected to servers of the attacker's choosing. This 'Kaminsky bug' was catalogued as CVE-2008-1447 and CERT Vulnerability Note VU#800113, and because it was rooted in the protocol design, it affected nearly every DNS server vendor and implementation, including BIND.

Rather than publishing the details immediately, Kaminsky worked with major vendors—including Microsoft, Cisco, and ISC (maintainer of BIND)—in a secret, coordinated effort, reportedly convened at Microsoft's headquarters, to develop and simultaneously release patches across the industry. On July 8, 2008, vendors released fixes together, primarily introducing source-port randomization as a mitigation while noting that DNSSEC offered the more definitive long-term solution. Kaminsky publicly detailed the flaw shortly afterward in a talk titled "Black Ops 2008: It's the End of the Cache as We Know It" at Black Hat USA, drawing an overflow crowd, and again at DEF CON 16 and Black Hat Japan.

Other Research and Public Interest Work

Kaminsky's other notable work included using DNS cache snooping techniques in 2005 to estimate the scale of computers infected by the controversial Sony BMG CD copy-protection rootkit, at several hundred thousand machines. In 2009, he helped identify a network-detectable signature for hosts infected by the Conficker worm, which was subsequently incorporated into scanning tools such as Nmap and Nessus. He also researched flaws in X.509 certificate parsing (with Meredith L. Patterson and Len Sassaman) and developed Interpolique, a framework aimed at helping developers prevent injection-style vulnerabilities such as SQL injection and cross-site scripting. He later served in an ICANN Trusted Community Representative role connected to the DNSSEC root key ceremony.

Death and Legacy

Kaminsky died on April 23, 2021, in San Francisco at age 42; his aunt, Dr. Toby Maurer, said the cause was diabetic ketoacidosis, a complication of diabetes. His death prompted extensive tributes across the security community, and The New York Times had previously described him as an "Internet security savior" and "digital Paul Revere" for his role in the 2008 DNS fix. Following his death, Human Security established the Dan Kaminsky Fellowship in his honor, and he was posthumously inducted into the Internet Hall of Fame in 2021.

Timeline

• 1979-02-07Born in San Francisco, California.
• 2005Used DNS cache snooping to estimate the number of computers infected by the Sony BMG rootkit at several hundred thousand.
• 2008-07-08Coordinated, multi-vendor patches for the DNS cache-poisoning flaw he discovered (CVE-2008-1447 / CERT VU#800113) were released simultaneously across the industry.
• 2008-08Publicly detailed the DNS vulnerability in the "Black Ops 2008" talk at Black Hat USA, and later at DEF CON 16 and Black Hat Japan.
• 2009Helped identify a network-detectable signature for Conficker-infected hosts, later integrated into Nmap and Nessus.
• 2021-04-23Died in San Francisco at age 42; cause reported as diabetic ketoacidosis.
• 2021Posthumously inducted into the Internet Hall of Fame; Human Security established the Dan Kaminsky Fellowship in his honor.