CVE-2018-20187
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely...
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
CVE-2018-20187- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:P/I:N/A:N - Weakness
- CWE-320
- Updated
- 2026-11-02
CVE List No score
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
CVE-2018-20187- Updated
- 2026-11-02
EUVDEUVD-2018-12754 No score
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
EUVD-2018-12754- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-g9j4-hp3j-g668
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely...
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
GHSA-g9j4-hp3j-g668- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVALPINE-CVE-2018-20187
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
ALPINE-CVE-2018-20187- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-03
OSV
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
CVE-2018-20187- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-20187
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
DEBIAN-CVE-2018-20187- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2018-20187
5.9
A side-channel issue was discovered in Botan before 2.9.0. An attacker capable of precisely measuring the time taken for ECC key generation may be able to derive information about the high bits of the secret key, as the function to derive the public point from the secret scalar uses an unblinded Montgomery ladder whose loop iteration count depends on the bitlength of the secret. This issue affects only key generation, not ECDSA signatures or ECDH key agreement.
- Record
UBUNTU-CVE-2018-20187- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVopenSUSE-SU-2024:10594-1 No score
Botan-2.18.1-1.3 on GA media
These are all security issues fixed in the Botan-2.18.1-1.3 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:10594-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
botanAlpine:v3.10 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.11 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.12 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.13 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.14 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.15 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.16 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.17 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.18 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.19 |
before 2.9.0-r0 | 2.9.0-r0 |
Show 7 moreShow less
| Package | Affected | Fixed |
|---|---|---|
botanAlpine:v3.20 |
before 2.9.0-r0 | 2.9.0-r0 |
botanAlpine:v3.21 |
before 2.9.0-r0 | 2.9.0-r0 |
botanDebian:12 |
before 2.9.0-2 | 2.9.0-2 |
botanDebian:13 |
before 2.9.0-2 | 2.9.0-2 |
botan1.10Ubuntu:Pro:14.04:LTS |
All versions, plus listed versions 1.10.5-11.10.5-1ubuntu11.10.5-1+deb7u1ubuntu0.14.04.11.10.5-1+deb7u1ubuntu0.14.04.1+esm1 |
None known |
botanUbuntu:18.04:LTS |
All versions, plus listed versions 2.4.0-32.4.0-42.4.0-5ubuntu1 |
None known |
BotanopenSUSE:Tumbleweed |
before 2.18.1-1.3 | 2.18.1-1.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | OSV | |
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-20187 is a medium vulnerability (CVSS 5.9) in Botan Project Botan, published March 8, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.52%, the 74th percentile. Fixed in botan 2.9.0-r0.
References
github.com/crocs-muni/ECTester
botan.randombit.net/news.html
botan.randombit.net/security.html
nvd.nist.gov/vuln/detail/CVE-2018-20187
github.com/advisories/GHSA-g9j4-hp3j-g668
security.alpinelinux.org/vuln/CVE-2018-20187
Show 12 moreShow less
security-tracker.debian.org/tracker/CVE-2018-20187
ubuntu.com/security/CVE-2018-20187
github.com/randombit/botan/pull/1792
github.com/randombit/botan/commit/70aa7303acfff9eefc24598c289a84db3579ebd1
cve.org/CVERecord?id=CVE-2018-20187
suse.com/security/cve/CVE-2016-9132
suse.com/security/cve/CVE-2017-14737
suse.com/security/cve/CVE-2017-2801
suse.com/security/cve/CVE-2018-12435
suse.com/security/cve/CVE-2018-20187
suse.com/security/cve/CVE-2018-9127
suse.com/security/cve/CVE-2018-9860