CVE-2018-20187: botan_project botan Key Management Errors
Vulnerability summary
CVE-2018-20187 is a medium (CVSS 5.9) Key Management Errors vulnerability in botan_project botan. EPSS estimates a 1.52% chance of exploitation in the next 30 days, higher than 74.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 08-03-2019PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- OSV · UbuntuEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS trend
Probability
1.52%
Chance of exploitation in the next 30 days
Percentile
74%
Versus all other CVEs
30-day change
+0.07 pp
From 1.45% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu2 products
- botanAll versions (No fix recorded)
- botan1.10All versions (No fix recorded)
Alpine1 product
- botan< 2.9.0-r0
Botan_project1 product
- botan< 2.9.0
Debian1 product
- botan< 2.9.0-2
4 vendors · 5 products
