{"id":"DEBIAN-CVE-2026-69249","details":"python-cryptography is a package designed to expose cryptographic primitives and recipes to Python developers. In versions 42.0.0 through 48.0.0, when resolving invalid certificate chains that include duplicate copies of self-signed certificates, the processing recursively invokes the same candidate, leading to an exponential blowup. Although the limitation that the chain depth cannot exceed a specified maximum depth prevents unbounded recursion and guarantees termination, an attacker-controlled certificate chain can lead the processing to easily take more than 5s to reject in testing. This amplification could form the basis for a resource exhaustion denial of service attack. The core issue arises in the recursive nature of build_chain_inner, which does not de-duplicate against previously analyzed candidates. As the correctness of validation is not affected, the integrity of a system cannot be compromised through this vector, only its availability. This issue is fixed in 49.0.0.","modified":"2026-09-11T18:47:28.515007481Z","published":"2026-08-03T22:16:52.720Z","upstream":["CVE-2026-69249"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-69249"}],"affected":[{"package":{"name":"python-cryptography","ecosystem":"Debian:12","purl":"pkg:deb/debian/python-cryptography?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["38.0.4-3","38.0.4-3+deb12u1","38.0.4-4","41.0.7-1","41.0.7-2","41.0.7-3","41.0.7-4","41.0.7-5","42.0.5-1","42.0.5-2","43.0.0-1","43.0.0-2","43.0.0-3","44.0.2-1","44.0.2-2","45.0.6-1","45.0.6-1~exp1","45.0.7-1","46.0.1-1","46.0.1-1~exp1","46.0.5-1","46.0.5-2","46.0.6-1","46.0.7-1","47.0.0-1","49.0.0-1","49.0.0-1~exp1","49.0.0-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-69249.json"}},{"package":{"name":"python-cryptography","ecosystem":"Debian:13","purl":"pkg:deb/debian/python-cryptography?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["43.0.0-3","43.0.0-3+deb13u1","44.0.2-1","44.0.2-2","45.0.6-1","45.0.6-1~exp1","45.0.7-1","46.0.1-1","46.0.1-1~exp1","46.0.5-1","46.0.5-2","46.0.6-1","46.0.7-1","47.0.0-1","49.0.0-1","49.0.0-1~exp1","49.0.0-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-69249.json"}},{"package":{"name":"python-cryptography","ecosystem":"Debian:14","purl":"pkg:deb/debian/python-cryptography?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"49.0.0-1"}]}],"versions":["43.0.0-3","44.0.2-1","44.0.2-2","45.0.6-1","45.0.6-1~exp1","45.0.7-1","46.0.1-1","46.0.1-1~exp1","46.0.5-1","46.0.5-2","46.0.6-1","46.0.7-1","47.0.0-1","49.0.0-1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-69249.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}