CVE catalog

CVE-2016-5420

curl: CVE-2016-5420

Severity: High · CVSS 7.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Published: Aug 3, 2016, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 15.36% · Oct 25, 2026

curl and libcurl before 7.50.1 do not check the client certificate when choosing the TLS connection to reuse, which might allow remote attackers to hijack the authentication of the connection by leveraging a previously created connection with a different client certificate.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	curl	sid	`8.23.0-1`	fixed
Debian	curl	forky	`8.22.0-1`	fixed
Debian	curl	trixie	`8.14.1-2+deb13u5`	fixed
Debian	curl	trixie-security	`8.14.1-2+deb13u7`	fixed
Debian	curl	bookworm	`7.88.1-10+deb12u15`	fixed
Debian	curl	bookworm-security	`7.88.1-10+deb12u5`	fixed
Alpine	curl	3.10	`7.50.1-r0`	fixed
Alpine	curl	3.11	`7.50.1`	fixed
Alpine	curl	3.12	`7.50.1-r0`	fixed
Alpine	curl	3.13	`7.50.1-r0`	fixed
Alpine	curl	3.14	`7.50.1-r0`	fixed
Alpine	curl	3.15	`7.50.1-r0`	fixed
Alpine	curl	3.16	`7.50.1-r0`	fixed
Alpine	curl	3.17	`7.50.1-r0`	fixed
Alpine	curl	3.18	`7.50.1-r0`	fixed
Alpine	curl	3.19	`7.50.1-r0`	fixed
Alpine	curl	3.2	`7.49.1-r1`	fixed
Alpine	curl	3.20	`7.50.1-r0`	fixed
Alpine	curl	3.21	`7.50.1-r0`	fixed
Alpine	curl	3.22	`7.50.1-r0`	fixed
Alpine	curl	3.23	`7.50.1-r0`	fixed
Alpine	curl	3.24	`7.50.1-r0`	fixed
Alpine	curl	3.3	`7.49.1-r1`	fixed
Alpine	curl	3.4	`7.50.1-r0`	fixed
Alpine	curl	3.5	`7.50.1-r0`	fixed
Alpine	curl	3.6	`7.50.1`	fixed
Alpine	curl	3.7	`7.50.1`	fixed
Alpine	curl	3.8	`7.50.1`	fixed
Alpine	curl	3.9	`7.50.1-r0`	fixed
Ubuntu	curl	14.04	`7.32.0-1ubuntu1`	vulnerable
Ubuntu	curl	14.04	`7.33.0-1ubuntu1`	vulnerable
Ubuntu	curl	14.04	`7.34.0-1ubuntu1`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu1`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.1`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.2`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.3`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.5`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.6`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.7`	vulnerable
Ubuntu	curl	14.04	`7.35.0-1ubuntu2.8`	fixed
Ubuntu	curl	16.04	`7.43.0-1ubuntu2`	vulnerable
Ubuntu	curl	16.04	`7.45.0-1ubuntu1`	vulnerable
Ubuntu	curl	16.04	`7.46.0-1ubuntu1`	vulnerable
Ubuntu	curl	16.04	`7.47.0-1ubuntu1`	vulnerable
Ubuntu	curl	16.04	`7.47.0-1ubuntu2`	vulnerable
Ubuntu	curl	16.04	`7.47.0-1ubuntu2.1`	fixed
Suse	curl	studio onsite 1.3	`7.19.7-1.20.47.2`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	curl	source	sid	`7.50.1-1`	not yet assigned	Not reported	Not reported
Debian	curl	source	forky	`7.50.1-1`	not yet assigned	Not reported	Not reported
Debian	curl	source	trixie	`7.50.1-1`	not yet assigned	Not reported	Not reported
Debian	curl	source	bookworm	`7.50.1-1`	not yet assigned	Not reported	Not reported
Alpine	curl	apk	3.10	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.11	`7.50.1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.12	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.13	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.14	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.15	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.16	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.17	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.18	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.19	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.2	`7.49.1-r1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.20	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.21	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.22	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.23	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.24	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.3	`7.49.1-r1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.4	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.5	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.6	`7.50.1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.7	`7.50.1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.8	`7.50.1`	Not reported	ALPINE-CVE-2016-5420	Not reported
Alpine	curl	apk	3.9	`7.50.1-r0`	Not reported	ALPINE-CVE-2016-5420	Not reported
Ubuntu	curl	deb	14.04	`7.35.0-1ubuntu2.8`	Not reported	UBUNTU-CVE-2016-5420	Not reported
Ubuntu	curl	deb	16.04	`7.47.0-1ubuntu2.1`	Not reported	UBUNTU-CVE-2016-5420	Not reported
Suse	curl	rpm	studio onsite 1.3	`7.19.7-1.20.47.2`	Not reported	SUSE-SU-2016:2700-1	Not reported

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[curl]Unknown
Details (6)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · amd64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · arm64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl3-gnutls]Unknown
Source package: [curl]
Details (6)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · amd64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · arm64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl3-nss]Unknown
Source package: [curl]
Details (4)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl4]Unknown
Source package: [curl]
Details (6)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · amd64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · arm64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl4-doc]Unknown
Source package: [curl]
Details (6)
- 7.88.1-10+deb12u15 · all · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · all · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · all · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · all · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · all · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · all · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl4-gnutls-dev]Unknown
Source package: [curl]
Details (6)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · amd64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · arm64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl4-nss-dev]Unknown
Source package: [curl]
Details (4)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
[libcurl4-openssl-dev]Unknown
Source package: [curl]
Details (6)
- 7.88.1-10+deb12u15 · amd64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u15 · arm64 · bookworm
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · amd64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 8.14.1-2+deb13u2~bpo13+1 · arm64 · bookworm-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · amd64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12
- 7.88.1-10+deb12u5 · arm64 · bookworm-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · bookworm; dsa · curl · debian · 12

[Debian 13 (Trixie)]

[curl]Unknown
Details (5)
- 8.14.1-2+deb13u4 · amd64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · arm64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · amd64 · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl3t64-gnutls]Unknown
Source package: [curl]
Details (5)
- 8.14.1-2+deb13u4 · amd64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · arm64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · amd64 · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl4-doc]Unknown
Source package: [curl]
Details (5)
- 8.14.1-2+deb13u4 · all · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · all · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · all · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · all · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · all · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl4-gnutls]Unknown
Source package: [curl]
Details (2)
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl4-gnutls-dev]Unknown
Source package: [curl]
Details (5)
- 8.14.1-2+deb13u4 · amd64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · arm64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · amd64 · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl4-openssl-dev]Unknown
Source package: [curl]
Details (5)
- 8.14.1-2+deb13u4 · amd64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · arm64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · amd64 · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
[libcurl4t64]Unknown
Source package: [curl]
Details (5)
- 8.14.1-2+deb13u4 · amd64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u4 · arm64 · trixie
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · amd64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.21.0-2~bpo13+1 · arm64 · trixie-backports
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13
- 8.14.1-2+deb13u7 · amd64 · trixie-security
  Fixed · Fixed: 7.50.1-1
  dsa · curl · debian · 13

Observed: Oct 23, 2026, 5:22:21 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]