libgcrypt: Possible timing attack on EdDSA session key
Published Jun 11, 2017
5.9
MEDIUMCVSS 3.0
EPSS 2.34%
Description
In Libgcrypt before 1.7.7, an attacker who learns the EdDSA session key (from side-channel observation during the signing process) can easily recover the long-term secret key. 1.7.7 makes a cipher/ecc-eddsa.c change to store this session key in secure memory, to ensure that constant-time point operations are used in the MPI library.
Affected products
No data.
No data.
Red Hat Enterprise Linux 5
libgcrypt
Not affected
Red Hat Enterprise Linux 6
libgcrypt
Not affected
Red Hat Enterprise Linux 7
libgcrypt
Not affected
Red Hat Enterprise Virtualization 3
mingw-virt-viewer
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | libgcrypt | Not affected | n/a |
| Red Hat Enterprise Linux 6 | libgcrypt | Not affected | n/a |
| Red Hat Enterprise Linux 7 | libgcrypt | Not affected | n/a |
| Red Hat Enterprise Virtualization 3 | mingw-virt-viewer | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue did not affect the versions of libgcrypt as shipped with Red Hat Enterprise Linux 5, 6 and 7 as they did not include support for EdDSA cipher.
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
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.34% (0.02337) | 82.97th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.32% (0.02318) | 81.15th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.39% (0.00388) | 57.83th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.40% (0.00402) | 74.50th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.40% (0.00402) | 72.97th | v3 (v2023.03.01) |
| Nov 8, 2023 | 0.40% (0.00402) | 70.70th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.39% (0.00392) | 70.03th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.44% (0.00444) | 70.93th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.11% (0.01108) | 55.18th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.11% (0.01108) | 29.61th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.66% (0.01659) | 34.20th | v5 (v2026.06.15) |
| Apr 14, 2021 | 1.66% (0.01659) | 0.00th | v1 |
References (11)
- http://www.debian.org/security/2017/dsa-3880 vendor-advisoryx_refsource_DEBIAN
- http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html x_refsource_CONFIRM
- http://www.securityfocus.com/bid/99046 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2017-9526 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1459887 Issue Tracking
- https://bugzilla.suse.com/show_bug.cgi?id=1042326 x_refsource_CONFIRMIssue TrackingPatch
- https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=5a22de904a0a366ae79f03ff1e13a1232a89e26b x_refsource_CONFIRM
- https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=f9494b3f258e01b6af8bd3941ce436bcc00afc56 x_refsource_CONFIRM
- https://nvd.nist.gov/vuln/detail/CVE-2017-9526
- https://www.cve.org/CVERecord?id=CVE-2017-9526
- https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html x_refsource_CONFIRM
| Link | Providers | Tags |
|---|---|---|
| http://www.debian.org/security/2017/dsa-3880 | vendor-advisoryx_refsource_DEBIAN | |
| http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html | x_refsource_CONFIRM | |
| http://www.securityfocus.com/bid/99046 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/security/cve/CVE-2017-9526 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1459887 | Issue Tracking | |
| https://bugzilla.suse.com/show_bug.cgi?id=1042326 | x_refsource_CONFIRMIssue TrackingPatch | |
| https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=5a22de904a0a366ae79f03ff1e13a1232a89e26b | x_refsource_CONFIRM | |
| https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=f9494b3f258e01b6af8bd3941ce436bcc00afc56 | x_refsource_CONFIRM | |
| https://nvd.nist.gov/vuln/detail/CVE-2017-9526 | ||
| https://www.cve.org/CVERecord?id=CVE-2017-9526 | ||
| https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html | x_refsource_CONFIRM |
Change history (0)
No recorded changes yet.