libssh2: bits/bytes confusion resulting in truncated Diffie-Hellman secret length
Published Apr 13, 2016
5.9
MEDIUMCVSS 3.0
EPSS 2.59%
Description
The diffie_hellman_sha256 function in kex.c in libssh2 before 1.7.0 improperly truncates secrets to 128 or 256 bits, which makes it easier for man-in-the-middle attackers to decrypt or intercept SSH sessions via unspecified vectors, aka a "bits/bytes confusion bug."
Affected products
No data.
Configuration 1
- 22
- 23
Configuration 4
- 7.0
- 8.0
No data.
Red Hat Enterprise Linux 6
libssh2-0:1.4.2-2.el6_7.1
Fixed · RHSA-2016:0428
Red Hat Enterprise Linux 7
libssh2-0:1.4.3-10.el7_2.1
Fixed · RHSA-2016:0428
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | libssh2-0:1.4.2-2.el6_7.1 | Fixed | RHSA-2016:0428 |
| Red Hat Enterprise Linux 7 | libssh2-0:1.4.3-10.el7_2.1 | Fixed | RHSA-2016:0428 |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
AV:N/AC:M/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
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 (16 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.59% (0.02591) | 84.75th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.70% (0.02697) | 83.92th | v5 (v2026.06.15) |
| Dec 1, 2025 | 4.06% (0.04065) | 88.17th | v4 (v2025.03.14) |
| Jul 25, 2025 | 2.30% (0.02297) | 84.03th | v4 (v2025.03.14) |
| Mar 30, 2025 | 4.06% (0.04064) | 87.46th | v4 (v2025.03.14) |
| Mar 29, 2025 | 8.51% (0.08509) | 87.08th | v4 (v2025.03.14) |
| Mar 17, 2025 | 3.15% (0.03147) | 86.02th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.55% (0.00550) | 78.26th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.55% (0.00550) | 76.80th | v3 (v2023.03.01) |
| Sep 24, 2023 | 0.55% (0.00550) | 74.73th | v3 (v2023.03.01) |
| Jun 6, 2023 | 0.39% (0.00388) | 69.36th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.27% (0.00273) | 62.91th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.54% (0.01537) | 74.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
References (17)
- http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177980.html vendor-advisoryx_refsource_FEDORA
- http://lists.fedoraproject.org/pipermail/package-announce/2016-March/178573.html vendor-advisoryx_refsource_FEDORA
- http://lists.opensuse.org/opensuse-updates/2016-03/msg00008.html vendor-advisoryx_refsource_SUSE
- http://www.debian.org/security/2016/dsa-3487 vendor-advisoryx_refsource_DEBIAN
- http://www.libssh2.org/adv_20160223.html
- http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html x_refsource_CONFIRM
- http://www.securityfocus.com/bid/82514 vdb-entryx_refsource_BID
- https://access.redhat.com/security/cve/CVE-2016-0787 Vendor Advisory
- https://bto.bluecoat.com/security-advisory/sa120 x_refsource_CONFIRM
- https://bugzilla.redhat.com/show_bug.cgi?id=1306021 Issue Tracking
- https://kc.mcafee.com/corporate/index?page=content&id=SB10156 x_refsource_CONFIRM
- https://nvd.nist.gov/vuln/detail/CVE-2016-0787
- https://puppet.com/security/cve/CVE-2016-0787 x_refsource_CONFIRM
- https://security.gentoo.org/glsa/201606-12 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2016-0787
- https://www.libssh2.org/CVE-2016-0787.patch x_refsource_CONFIRMPatch
- https://www.libssh2.org/adv_20160223.html x_refsource_CONFIRMVendor Advisory
Change history (0)
No recorded changes yet.