CVE-2016-0799

The fmtstr function in crypto/bio/b_print.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g improperly calculates string lengths, which allows remote attackers to cause a denial of service (overflow and out-of-bounds read) or possibly have unspecified other impact via a long string, as demonstrated by a large amount of ASN.1 data, a different vulnerability than CVE-2016-2842.

Published: 2016-03-03 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2016-0799 is rated High Risk (68.3/100): CVSS Critical severity, with high exploitation likelihood (EPSS 43.54%, 97th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-0799

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-04 53.56% 43.54% -10.03%
2 2026-03-01 43.54% 53.56% +10.03%
3 2026-02-08 43.54%

Full EPSS history (44 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-0799

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
10.0 10.0 [email protected]

Weakness enumeration for CVE-2016-0799

OS Trackers for CVE-2016-0799

vendor priority summary link
debian not yet assigned CVE-2016-0799 not yet assigned priority: Debian including 1 source packages (openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-0799
gentoo normal CVE-2016-0799: 1 GLSA(s) (201603-15), 1 atom(s) (dev-libs/openssl); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2016-0799
redhat low https://access.redhat.com/security/cve/CVE-2016-0799
suse medium CVE-2016-0799 severity moderate: SUSE including 98 source package names (compat-openssl097g-0.9.7g-146.22.41.1, compat-openssl097g-32bit-0.9.7g-146.22.41.1, …), 293 product×package rows across 52 product lines (Image SLES12-SP5-Azure-SAP-BYOS, Image SLES12-SP5-Azure-SAP-On-Demand, … (52 product lines)): Fixed 200, Known Not Affected 93. https://www.suse.com/security/cve/CVE-2016-0799/
ubuntu low CVE-2016-0799 low priority: Ubuntu including 2 source packages (openssl, openssl098), 22 status rows across 11 suites (artful, bionic, cosmic, disco, precise, trusty, upstream, wily, xenial, yakkety, zesty): released 10, DNE 9, needs-triage 2, ignored 1. https://ubuntu.com/security/CVE-2016-0799

Affected software / configurations for CVE-2016-0799

Vendor Product Version Raw CPE
openssl openssl 1.0.1 cpe:2.3:a:openssl:openssl:1.0.1:*:*:*:*:*:*:*
openssl openssl 1.0.1 cpe:2.3:a:openssl:openssl:1.0.1:beta1:*:*:*:*:*:*
openssl openssl 1.0.1 cpe:2.3:a:openssl:openssl:1.0.1:beta2:*:*:*:*:*:*
openssl openssl 1.0.1 cpe:2.3:a:openssl:openssl:1.0.1:beta3:*:*:*:*:*:*
openssl openssl 1.0.1a cpe:2.3:a:openssl:openssl:1.0.1a:*:*:*:*:*:*:*
openssl openssl 1.0.1b cpe:2.3:a:openssl:openssl:1.0.1b:*:*:*:*:*:*:*
openssl openssl 1.0.1c cpe:2.3:a:openssl:openssl:1.0.1c:*:*:*:*:*:*:*
openssl openssl 1.0.1d cpe:2.3:a:openssl:openssl:1.0.1d:*:*:*:*:*:*:*
openssl openssl 1.0.1e cpe:2.3:a:openssl:openssl:1.0.1e:*:*:*:*:*:*:*
openssl openssl 1.0.1f cpe:2.3:a:openssl:openssl:1.0.1f:*:*:*:*:*:*:*
openssl openssl 1.0.1g cpe:2.3:a:openssl:openssl:1.0.1g:*:*:*:*:*:*:*
openssl openssl 1.0.1h cpe:2.3:a:openssl:openssl:1.0.1h:*:*:*:*:*:*:*
openssl openssl 1.0.1i cpe:2.3:a:openssl:openssl:1.0.1i:*:*:*:*:*:*:*
openssl openssl 1.0.1j cpe:2.3:a:openssl:openssl:1.0.1j:*:*:*:*:*:*:*
openssl openssl 1.0.1k cpe:2.3:a:openssl:openssl:1.0.1k:*:*:*:*:*:*:*
openssl openssl 1.0.1l cpe:2.3:a:openssl:openssl:1.0.1l:*:*:*:*:*:*:*
openssl openssl 1.0.1m cpe:2.3:a:openssl:openssl:1.0.1m:*:*:*:*:*:*:*
openssl openssl 1.0.1n cpe:2.3:a:openssl:openssl:1.0.1n:*:*:*:*:*:*:*
openssl openssl 1.0.1o cpe:2.3:a:openssl:openssl:1.0.1o:*:*:*:*:*:*:*
openssl openssl 1.0.1p cpe:2.3:a:openssl:openssl:1.0.1p:*:*:*:*:*:*:*
openssl openssl 1.0.1q cpe:2.3:a:openssl:openssl:1.0.1q:*:*:*:*:*:*:*
openssl openssl 1.0.1r cpe:2.3:a:openssl:openssl:1.0.1r:*:*:*:*:*:*:*
openssl openssl 1.0.2 cpe:2.3:a:openssl:openssl:1.0.2:*:*:*:*:*:*:*
openssl openssl 1.0.2 cpe:2.3:a:openssl:openssl:1.0.2:beta1:*:*:*:*:*:*
openssl openssl 1.0.2 cpe:2.3:a:openssl:openssl:1.0.2:beta2:*:*:*:*:*:*
openssl openssl 1.0.2 cpe:2.3:a:openssl:openssl:1.0.2:beta3:*:*:*:*:*:*
openssl openssl 1.0.2a cpe:2.3:a:openssl:openssl:1.0.2a:*:*:*:*:*:*:*
openssl openssl 1.0.2b cpe:2.3:a:openssl:openssl:1.0.2b:*:*:*:*:*:*:*
openssl openssl 1.0.2c cpe:2.3:a:openssl:openssl:1.0.2c:*:*:*:*:*:*:*
openssl openssl 1.0.2d cpe:2.3:a:openssl:openssl:1.0.2d:*:*:*:*:*:*:*
openssl openssl 1.0.2e cpe:2.3:a:openssl:openssl:1.0.2e:*:*:*:*:*:*:*
openssl openssl 1.0.2f cpe:2.3:a:openssl:openssl:1.0.2f:*:*:*:*:*:*:*
pulsesecure client cpe:2.3:a:pulsesecure:client:-:*:*:*:*:android:*:*
pulsesecure client cpe:2.3:a:pulsesecure:client:-:*:*:*:*:iphone_os:*:*
pulsesecure steel_belted_radius cpe:2.3:a:pulsesecure:steel_belted_radius:-:*:*:*:*:*:*:*

References for CVE-2016-0799

URL Tags
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759
http://lists.fedoraproject.org/pipermail/package-announce/2016-March/178358.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-March/178817.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00001.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00003.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00004.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00006.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00007.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00009.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00011.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00012.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00017.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00025.html
http://lists.opensuse.org/opensuse-security-announce/2016-04/msg00038.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00015.html
http://lists.opensuse.org/opensuse-security-announce/2016-05/msg00017.html
http://marc.info/?l=bugtraq&m=145983526810210&w=2
http://marc.info/?l=bugtraq&m=146108058503441&w=2
http://openssl.org/news/secadv/20160301.txt Vendor Advisory
http://rhn.redhat.com/errata/RHSA-2016-0722.html
http://rhn.redhat.com/errata/RHSA-2016-0996.html
http://rhn.redhat.com/errata/RHSA-2016-2073.html
http://rhn.redhat.com/errata/RHSA-2016-2957.html
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160302-openssl
http://www.debian.org/security/2016/dsa-3500
http://www.oracle.com/technetwork/security-advisory/cpuapr2016v3-2985753.html
http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
http://www.oracle.com/technetwork/topics/security/bulletinjan2016-2867206.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
http://www.securityfocus.com/bid/83755
http://www.securityfocus.com/bid/91787
http://www.securitytracker.com/id/1035133
http://www.ubuntu.com/usn/USN-2914-1
https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=578b956fe741bf8e84055547b1e83c28dd902c73
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03741en_us
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05068681
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05086877
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05111017
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05126404
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05131085
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05135617
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05141441
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05150736
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05150800
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05150888
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05157667
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05158380
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05376917
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA40168
https://security.FreeBSD.org/advisories/FreeBSD-SA-16:12.openssl.asc
https://security.gentoo.org/glsa/201603-15
https://www.openssl.org/news/secadv/20160301.txt
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