CVE-2017-9526

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.

Published: 2017-06-11 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-9526 is rated Moderate Risk (48.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.65%). Review affected assets and schedule 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-2017-9526

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 2025-11-21 0.45% 0.65% +0.20%
2 2025-11-18 0.65% 0.45% -0.20%
3 2025-08-30 — 0.65% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-9526

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2017-9526

OS Trackers for CVE-2017-9526

vendor priority summary link
debian not yet assigned CVE-2017-9526 not yet assigned priority: Debian including 1 source packages (libgcrypt20), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-9526
redhat low — https://access.redhat.com/security/cve/CVE-2017-9526
suse medium CVE-2017-9526 severity moderate: SUSE including 22 source package names (0.9.1:libgcrypt20-1.6.1-16.39.1, 1.0.0:libgcrypt20-1.6.1-16.39.1, …), 63 product×package rows across 50 product lines (Container caasp/v4/default-http-backend, Container caasp/v4/dnsmasq-nanny, … (50 product lines)): Fixed 53, Known Not Affected 10. https://www.suse.com/security/cve/CVE-2017-9526/
ubuntu low CVE-2017-9526 low priority: Ubuntu including 2 source packages (libgcrypt11, libgcrypt20), 18 status rows across 9 suites (artful, bionic, cosmic, disco, trusty, upstream, xenial, yakkety, zesty): DNE 8, not-affected 6, released 4. https://ubuntu.com/security/CVE-2017-9526

Affected software / configurations for CVE-2017-9526

Vendor Product Version Raw CPE
gnupg libgcrypt <= 1.7.6 cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*

References for CVE-2017-9526

cvelogic Threat Intelligence