CRITICAL
openssl: Integer overflow in MDC2_Update()
Published Sep 16, 2016
9.8
CRITICALCVSS 3.1
EPSS 31.99%
Description
Integer overflow in the MDC2_Update function in crypto/mdc2/mdc2dgst.c in OpenSSL before 1.1.0 allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors.
Affected products
No data.
Configuration 1
Configuration 2
OR
- 1.0.1
- 1.0.1a
- 1.0.1b
- 1.0.1c
- 1.0.1d
- 1.0.1e
- 1.0.1f
- 1.0.1g
- 1.0.1h
- 1.0.1i
- 1.0.1j
- 1.0.1k
- 1.0.1l
- 1.0.1m
- 1.0.1n
- 1.0.1o
- 1.0.1p
- 1.0.1q
- 1.0.1r
- 1.0.1s
- 1.0.1t
- 1.0.2
- 1.0.2a
- 1.0.2b
- 1.0.2c
- 1.0.2d
- 1.0.2e
- 1.0.2f
- 1.0.2g
- 1.0.2h
No data.
Red Hat Enterprise Linux 5
openssl
Not affected
Red Hat Enterprise Linux 5
openssl097a
Not affected
Red Hat Enterprise Linux 6
openssl
Not affected
Red Hat Enterprise Linux 6
openssl098e
Not affected
Red Hat Enterprise Linux 7
OVMF
Not affected
Red Hat Enterprise Linux 7
openssl
Not affected
Red Hat Enterprise Linux 7
openssl098e
Not affected
Red Hat JBoss Enterprise Application Platform 6
openssl
Not affected
Red Hat JBoss Enterprise Web Server 1
openssl
Not affected
Red Hat JBoss Enterprise Web Server 2
openssl
Not affected
Red Hat JBoss Enterprise Web Server 3
openssl
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 5 | openssl097a | Not affected | n/a |
| Red Hat Enterprise Linux 6 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 6 | openssl098e | Not affected | n/a |
| Red Hat Enterprise Linux 7 | OVMF | Not affected | n/a |
| Red Hat Enterprise Linux 7 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 7 | openssl098e | Not affected | n/a |
| Red Hat JBoss Enterprise Application Platform 6 | openssl | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 1 | openssl | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 2 | openssl | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 3 | openssl | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Not vulnerable. This issue did not affect the versions of openssl as shipped with Red Hat Enterprise Linux 4, 5, 6, and 7, as they did not include support for MDC-2.
Metrics
No CVSS v4.0 score for this CVE.
9.8 CRITICAL NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact High
Integrity Impact High
Availability Impact High
6.5 MEDIUM Red Hat
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact Low
Availability Impact Low
7.5 HIGH NVD
AV:N/AC:L/Au:N/C:P/I:P/A:P
Access Vector Network
Access Complexity Low
Authentication None
Confidentiality Impact Partial
Integrity Impact Partial
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
31.99% 0.31985
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.31985
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (51 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 31.99% (0.31985) | 98.26th | v5 (v2026.06.15) |
| Jun 15, 2026 | 31.99% (0.31985) | 98.08th | v5 (v2026.06.15) |
| May 29, 2026 | 28.00% (0.28004) | 96.56th | v4 (v2025.03.14) |
| Apr 21, 2026 | 26.22% (0.26222) | 96.31th | v4 (v2025.03.14) |
| Mar 8, 2026 | 28.55% (0.28546) | 96.44th | v4 (v2025.03.14) |
| Mar 4, 2026 | 26.67% (0.26674) | 96.23th | v4 (v2025.03.14) |
| Mar 1, 2026 | 9.86% (0.09858) | 92.88th | v4 (v2025.03.14) |
| Feb 18, 2026 | 28.82% (0.28821) | 96.44th | v4 (v2025.03.14) |
| Feb 4, 2026 | 34.86% (0.34856) | 96.90th | v4 (v2025.03.14) |
| Feb 1, 2026 | 13.06% (0.13056) | 93.94th | v4 (v2025.03.14) |
| Jan 14, 2026 | 34.86% (0.34856) | 96.88th | v4 (v2025.03.14) |
| Jan 4, 2026 | 32.88% (0.32879) | 96.73th | v4 (v2025.03.14) |
| Jan 1, 2026 | 12.03% (0.12025) | 93.59th | v4 (v2025.03.14) |
| Dec 28, 2025 | 32.88% (0.32879) | 96.72th | v4 (v2025.03.14) |
| Dec 27, 2025 | 34.39% (0.34390) | 96.86th | v4 (v2025.03.14) |
| Dec 4, 2025 | 32.88% (0.32879) | 96.69th | v4 (v2025.03.14) |
| Dec 1, 2025 | 12.31% (0.12309) | 93.63th | v4 (v2025.03.14) |
| Nov 4, 2025 | 32.88% (0.32879) | 96.67th | v4 (v2025.03.14) |
| Nov 1, 2025 | 12.03% (0.12025) | 93.53th | v4 (v2025.03.14) |
| Oct 28, 2025 | 32.88% (0.32879) | 96.66th | v4 (v2025.03.14) |
| Oct 27, 2025 | 34.39% (0.34390) | 96.80th | v4 (v2025.03.14) |
| Oct 4, 2025 | 32.88% (0.32879) | 96.73th | v4 (v2025.03.14) |
| Oct 1, 2025 | 12.03% (0.12025) | 93.56th | v4 (v2025.03.14) |
| Sep 4, 2025 | 34.39% (0.34390) | 96.86th | v4 (v2025.03.14) |
| Sep 1, 2025 | 14.34% (0.14335) | 94.20th | v4 (v2025.03.14) |
| Aug 4, 2025 | 34.39% (0.34390) | 96.82th | v4 (v2025.03.14) |
| Aug 1, 2025 | 14.34% (0.14335) | 94.16th | v4 (v2025.03.14) |
| Jul 30, 2025 | 34.39% (0.34390) | 96.82th | v4 (v2025.03.14) |
| Jul 4, 2025 | 32.01% (0.32009) | 96.60th | v4 (v2025.03.14) |
| Jul 1, 2025 | 11.48% (0.11477) | 93.31th | v4 (v2025.03.14) |
| Jun 26, 2025 | 32.01% (0.32009) | 96.59th | v4 (v2025.03.14) |
| Jun 4, 2025 | 14.70% (0.14704) | 94.12th | v4 (v2025.03.14) |
| Jun 1, 2025 | 4.34% (0.04342) | 88.40th | v4 (v2025.03.14) |
| May 4, 2025 | 14.70% (0.14704) | 94.08th | v4 (v2025.03.14) |
| May 1, 2025 | 4.34% (0.04342) | 88.32th | v4 (v2025.03.14) |
| Mar 30, 2025 | 15.04% (0.15038) | 94.00th | v4 (v2025.03.14) |
| Mar 29, 2025 | 23.99% (0.23989) | 93.63th | v4 (v2025.03.14) |
| Mar 17, 2025 | 14.70% (0.14704) | 93.98th | v4 (v2025.03.14) |
| Dec 17, 2024 | 23.85% (0.23849) | 96.60th | v3 (v2023.03.01) |
| Feb 27, 2024 | 28.94% (0.28939) | 96.73th | v3 (v2023.03.01) |
| Dec 18, 2023 | 22.66% (0.22665) | 96.05th | v3 (v2023.03.01) |
| Sep 29, 2023 | 20.67% (0.20672) | 95.77th | v3 (v2023.03.01) |
| Aug 20, 2023 | 18.25% (0.18246) | 95.52th | v3 (v2023.03.01) |
| Jul 8, 2023 | 2.79% (0.02788) | 89.18th | v3 (v2023.03.01) |
| May 8, 2023 | 2.20% (0.02196) | 87.73th | v3 (v2023.03.01) |
| Apr 20, 2023 | 2.19% (0.02186) | 87.72th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.55% (0.01553) | 85.10th | v3 (v2023.03.01) |
| Mar 6, 2023 | 7.56% (0.07559) | 92.87th | v2 (v2022.01.01) |
| Dec 14, 2022 | 7.56% (0.07559) | 92.66th | v2 (v2022.01.01) |
| Apr 1, 2022 | 6.58% (0.06584) | 90.55th | v2 (v2022.01.01) |
| Feb 4, 2022 | 6.58% (0.06584) | 78.46th | v2 (v2022.01.01) |
Weaknesses (2)
References (22)
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759 Third Party Advisory
- http://www-01.ibm.com/support/docview.wss?uid=swg21995039 Third Party Advisory
- http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html PatchThird Party Advisory
- http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html PatchThird Party Advisory
- http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html PatchThird Party Advisory
- http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html PatchThird Party Advisory
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html PatchThird Party Advisory
- http://www.securityfocus.com/bid/92984 vdb-entryThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1036885 vdb-entryThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2016-6303 Vendor Advisory
- https://bto.bluecoat.com/security-advisory/sa132 Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1370146 Issue TrackingPatchThird Party Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
- https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=55d83bf7c10c7b205fffa23fa7c3977491e56c07
- https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA40312 Third Party Advisory
- https://nodejs.org/en/blog/vulnerability/september-2016-security-releases/ Third Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2016-6303
- https://security.FreeBSD.org/advisories/FreeBSD-SA-16:26.openssl.asc vendor-advisoryThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2016-6303
- https://www.tenable.com/security/tns-2016-16 Third Party Advisory
- https://www.tenable.com/security/tns-2016-20 Third Party Advisory
- https://www.tenable.com/security/tns-2016-21 Third Party Advisory
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner redhat
Published Sep 16, 2016
Updated Aug 6, 2024
Reserved Jul 26, 2016
Link CVE-2016-6303
CISA Vulnrichment
Updated n/a