CVE-2016-0799
CVE-2016-0799 is a critical-severity vulnerability in Openssl with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 32% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-119.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 10.0
- EPSS exploit prediction: 32% (98th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Openssl
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2016-0799?
- CVE-2016-0799 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2016-0799 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 32% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2016-0799?
- CVE-2016-0799 primarily affects Openssl. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2016-0799?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2016-0799 published?
- CVE-2016-0799 was published on 2016-03-03 and last updated on 2026-06-17.
References
- 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
- 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
Affected products (35)
- cpe:2.3:a:openssl:openssl:1.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1:beta1:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1:beta2:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1:beta3:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1a:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1b:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1c:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1d:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1e:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1f:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1g:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1h:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1i:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1j:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1k:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1l:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1m:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1n:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1o:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1p:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1q:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.1r:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2:beta1:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2:beta2:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2:beta3:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2a:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2b:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2c:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2d:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2e:*:*:*:*:*:*:*
- cpe:2.3:a:openssl:openssl:1.0.2f:*:*:*:*:*:*:*
- cpe:2.3:a:pulsesecure:client:-:*:*:*:*:android:*:*
- cpe:2.3:a:pulsesecure:client:-:*:*:*:*:iphone_os:*:*
- cpe:2.3:a:pulsesecure:steel_belted_radius:-:*:*:*:*:*:*:*
More vulnerabilities in Openssl
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- CVE-2006-3738 — Critical (CVSS 10.0): Buffer overflow in the SSL_get_shared_ciphers function in OpenSSL 0.9.7 before 0.9.7l, 0.9.8 before 0.9.8d, and earlier…
- CVE-2026-31789 — Critical (CVSS 9.8): Issue summary: Converting an excessively large OCTET STRING value to a hexadecimal string leads to a heap buffer…
- CVE-2022-2274 — Critical (CVSS 9.8): The OpenSSL 3.0.4 release introduced a serious bug in the RSA implementation for X86_64 CPUs supporting the AVX512IFMA…
- CVE-2021-3711 — Critical (CVSS 9.8): In order to decrypt SM2 encrypted data an application is expected to call the API function EVP_PKEY_decrypt().…
- CVE-2016-6309 — Critical (CVSS 9.8): statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote…
Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities
- CVE-2026-2778 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in…
- CVE-2026-2776 — Critical (CVSS 10.0): Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability…
- CVE-2025-1866 — Critical (CVSS 10.0): Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in warmcat libwebsockets allows…
- CVE-2022-27625 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
- CVE-2022-27624 — Critical (CVSS 10.0): A vulnerability regarding improper restriction of operations within the bounds of a memory buffer is found in the…
- CVE-2020-11896 — Critical (CVSS 10.0): The Treck TCP/IP stack before 6.0.1.66 allows Remote Code Execution, related to IPv4 tunneling.
Threat intelligence
Threat-intel indicators referencing this CVE:
- 218.4.91.163 (ipv4-addr)
- 200.77.172.159 (ipv4-addr)
- 200.196.50.91 (ipv4-addr)
- 166.62.41.190 (ipv4-addr)
- 50.62.22.47 (ipv4-addr)
- 191.101.33.225 (ipv4-addr)
- 122.3.106.113 (ipv4-addr)