CVE-2023-50868

Name	CVE-2023-50868
Description	The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-3736-1, DLA-3816-1, DLA-3859-1, DSA-5620-1, DSA-5621-1, DSA-5626-1, DSA-5633-1, ELA-1046-1, ELA-1094-1, ELA-1165-1
Debian Bugs	1063845, 1063852, 1077751

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
bind9 (PTS)	jessie, jessie (lts)	1:9.9.5.dfsg-9+deb8u31	fixed
	stretch (security)	1:9.10.3.dfsg.P4-12.3+deb9u12	vulnerable
	stretch (lts), stretch	1:9.10.3.dfsg.P4-12.3+deb9u16	fixed
	buster, buster (lts)	1:9.11.5.P4+dfsg-5.1+deb10u13	fixed
	buster (security)	1:9.11.5.P4+dfsg-5.1+deb10u11	fixed
	bullseye	1:9.16.50-1~deb11u2	fixed
	bullseye (security)	1:9.16.50-1~deb11u1	fixed
	bookworm (security), bookworm	1:9.18.28-1~deb12u2	fixed
	sid, trixie	1:9.20.2-1	fixed
dnsjava (PTS)	jessie	2.1.5-0.1	vulnerable
	stretch	2.1.8-1	vulnerable
	sid, buster, bullseye, bookworm	2.1.8-2	vulnerable
dnsmasq (PTS)	jessie, jessie (lts)	2.72-3+deb8u7	vulnerable
	stretch (security)	2.76-5+deb9u3	vulnerable
	stretch (lts), stretch	2.76-5+deb9u4	vulnerable
	buster, buster (lts)	2.80-1+deb10u2	vulnerable
	buster (security)	2.80-1+deb10u1	vulnerable
	bullseye	2.85-1	vulnerable
	bookworm	2.89-1	vulnerable
	sid, trixie	2.90-4	fixed
knot-resolver (PTS)	buster (security), buster, buster (lts)	3.2.1-3+deb10u2	vulnerable
	bullseye	5.3.1-1+deb11u1	vulnerable
	bookworm (security), bookworm	5.6.0-1+deb12u1	fixed
	sid, trixie	5.7.4-2	fixed
pdns-recursor (PTS)	jessie, jessie (lts)	3.6.2-2+deb8u4	vulnerable
	buster (security), buster, buster (lts)	4.1.11-1+deb10u2	vulnerable
	bullseye	4.4.2-3	vulnerable
	bookworm (security), bookworm	4.8.8-1	fixed
	sid, trixie	5.1.3-1	fixed
systemd (PTS)	jessie, jessie (lts)	215-17+deb8u15	fixed
	stretch (security)	232-25+deb9u14	vulnerable
	stretch (lts), stretch	232-25+deb9u17	fixed
	buster, buster (lts)	241-7~deb10u11	fixed
	buster (security)	241-7~deb10u10	vulnerable
	bullseye	247.3-7+deb11u5	vulnerable
	bullseye (security)	247.3-7+deb11u6	fixed
	bookworm	252.31-1~deb12u1	fixed
	sid, trixie	257~rc2-3	fixed
unbound (PTS)	jessie, jessie (lts)	1.4.22-3+deb8u4	vulnerable
	stretch	1.6.0-3+deb9u2	vulnerable
	buster, buster (lts)	1.9.0-2+deb10u5	fixed
	buster (security)	1.9.0-2+deb10u4	fixed
	bullseye	1.13.1-1+deb11u2	fixed
	bullseye (security)	1.13.1-1+deb11u4	fixed
	bookworm (security), bookworm	1.17.1-2+deb12u2	fixed
	sid, trixie	1.22.0-1	fixed
unbound1.9 (PTS)	stretch (security)	1.9.0-2+deb10u2~deb9u2	vulnerable
	stretch (lts), stretch	1.9.0-2+deb10u2~deb9u4	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
bind9	source	jessie	9.9.5.dfsg-9+deb8u31		ELA-1094-1
bind9	source	stretch	1:9.10.3.dfsg.P4-12.3+deb9u16		ELA-1094-1
bind9	source	buster	1:9.11.5.P4+dfsg-5.1+deb10u11		DLA-3816-1
bind9	source	bullseye	1:9.16.48-1		DSA-5621-1
bind9	source	bookworm	1:9.18.24-1		DSA-5621-1
bind9	source	(unstable)	1:9.19.21-1
dnsjava	source	jessie	(unfixed)	end-of-life
dnsjava	source	stretch	(unfixed)	end-of-life
dnsjava	source	buster	(unfixed)	end-of-life
dnsjava	source	(unstable)	(unfixed)			1077751
dnsmasq	source	(unstable)	2.90-1
knot-resolver	source	bookworm	5.6.0-1+deb12u1		DSA-5633-1
knot-resolver	source	(unstable)	5.7.1-1
pdns-recursor	source	jessie	(unfixed)	end-of-life
pdns-recursor	source	buster	(unfixed)	end-of-life
pdns-recursor	source	bullseye	(unfixed)	end-of-life
pdns-recursor	source	bookworm	4.8.6-1		DSA-5626-1
pdns-recursor	source	(unstable)	4.9.3-1			1063852
systemd	source	jessie	(not affected)
systemd	source	stretch	232-25+deb9u17		ELA-1165-1
systemd	source	buster	241-7~deb10u11		ELA-1165-1
systemd	source	bullseye	247.3-7+deb11u6		DLA-3859-1
systemd	source	bookworm	252.23-1~deb12u1
systemd	source	(unstable)	255.4-1
unbound	source	jessie	(unfixed)	end-of-life
unbound	source	stretch	(unfixed)	end-of-life
unbound	source	buster	1.9.0-2+deb10u4		DLA-3736-1
unbound	source	bullseye	1.13.1-1+deb11u2		DSA-5620-1
unbound	source	bookworm	1.17.1-2+deb12u2		DSA-5620-1
unbound	source	(unstable)	1.19.1-1			1063845
unbound1.9	source	stretch	1.9.0-2+deb10u2~deb9u4		ELA-1046-1
unbound1.9	source	(unstable)	(unfixed)

Notes

[bookworm] - dnsmasq <no-dsa> (Update proposed for next point release)
[bullseye] - knot-resolver <ignored> (Too intrusive to backport, if DNSSEC is used Bookworm can be used)
[buster] - knot-resolver <ignored> (Too intrusive to backport, if DNSSEC is used Bookworm can be used)
[bullseye] - pdns-recursor <end-of-life> (No longer supported with security updates in Bullseye)
[buster] - systemd <no-dsa> (DNSSEC is disabled by default in systemd-resolved; can be fixed via point release)
[bookworm] - dnsjava <no-dsa> (Minor issue)
[bullseye] - dnsjava <no-dsa> (Minor issue)
https://kb.isc.org/docs/cve-2023-50868
https://downloads.isc.org/isc/bind9/9.16.48/patches/0005-CVE-2023-50387-CVE-2023-50868.patch
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html
https://www.knot-resolver.cz/2024-02-13-knot-resolver-5.7.1.html
https://github.com/CZ-NIC/knot-resolver/commit/e966b7fdb167add0ec37c56a954c2d847f627985 (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/eccb8e278c1cde0548cc570eac619feaa290cede (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/b5051ac26f34358b40f9115f977fe1f54e8f581e (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/24699e9f206a8f957b516cad22a8e5790d226836 (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/a05cf1d379d1af0958587bd111f791b72f404364 (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/9b421cdf91f987e0254a06ff2c4e8fbf76dc2b58 (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/5e80624b18d40ae44be704751d3b22943edf287f
https://github.com/CZ-NIC/knot-resolver/commit/f9ba52e6f54bc1db122870df50cb364cb977436e (v5.7.1)
https://github.com/CZ-NIC/knot-resolver/commit/b044babbee358dc305d770a1dab3a877c49468a7 (v5.7.1)
https://blog.powerdns.com/2024/02/13/powerdns-recursor-4-8-6-4-9-3-5-0-2-released
Fixed by: https://github.com/PowerDNS/pdns/pull/13781
https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/
https://nlnetlabs.nl/downloads/unbound/CVE-2023-50387_CVE-2023-50868.txt
Fixed by: https://github.com/NLnetLabs/unbound/commit/92f2a1ca690a44880f4c4fa70a4b5a4b029aaf1c (release-1.19.1)
https://github.com/systemd/systemd/issues/31413
https://github.com/systemd/systemd/commit/67d0ce8843d612a2245d0966197d4f528b911b66 (v256)
https://github.com/systemd/systemd/commit/eba291124bc11f03732d1fc468db3bfac069f9cb (v256)
https://github.com/systemd/systemd-stable/commit/1ebdb19ff194120109b08bbf888bdcc502f83211 (v255.4)
https://github.com/systemd/systemd-stable/commit/572692f0bdd6a3fabe3dd4a3e8e5565cc69b5e14 (v255.4)
https://github.com/systemd/systemd-stable/commit/2f5edffa8ffd5210165ebe7604f07d23f375fe9a (v254.10)
https://github.com/systemd/systemd-stable/commit/9899281c59a91f19c8b39362d203e997d2faf233 (v254.10)
https://github.com/systemd/systemd-stable/commit/7886eea2425fe7773cc012da0b2e266e33d4be12 (v253.17)
https://github.com/systemd/systemd-stable/commit/156e519d990a5662c719a1cbe80c6a02a2b9115f (v253.17)
https://github.com/systemd/systemd-stable/commit/7633d969f3422f9ad380a512987d398e54764817 (v252.23)
https://github.com/systemd/systemd-stable/commit/b43bcb51ebf9aea21b1e280e1872056994e3f53d (v252.23)
systemd: DNSSEC is default to off in systemd-resolved
https://github.com/advisories/GHSA-mmwx-rj87-vfgr
https://github.com/dnsjava/dnsjava/commit/711af79be3214f52daa5c846b95766dc0a075116 (v3.6.0)
[jessie] - systemd <not-affected> (DNSSEC support added in v229)