CVE-2018-9860

An issue was discovered in Botan 1.11.32 through 2.x before 2.6.0. An off-by-one error when processing malformed TLS-CBC ciphertext could cause the receiving side to include in the HMAC computation exactly 64K bytes of data following the record buffer, aka an over-read. The MAC comparison will subsequently fail and the connection will be closed. This could be used for denial of service. No information leak occurs.

Published: 2018-04-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2018-9860 is rated Moderate Risk (50.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.38%). Mandatory action: 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-2018-9860

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 2026-05-26 0.50% 0.38% -0.11%
2 2025-11-21 0.38% 0.50% +0.11%
3 2025-11-18 0.38%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-9860

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2018-9860

OS Trackers for CVE-2018-9860

vendor priority summary link
alpine high CVE-2018-9860: 1 source package rows (botan); 12 state rows across 8 repos (3.11-main, 3.12-main, 3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, edge-main); fixed 8, open 4. https://security.alpinelinux.org/vuln/CVE-2018-9860
debian not yet assigned CVE-2018-9860 not yet assigned priority: Debian including 1 source packages (botan), 3 status rows across 3 suites (bookworm, bullseye, trixie): resolved 3. https://security-tracker.debian.org/tracker/CVE-2018-9860
ubuntu medium CVE-2018-9860 medium priority: Ubuntu including 2 source packages (botan, botan1.10), 40 status rows across 20 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 17, not-affected 17, ignored 3, needed 1, needs-triage 1, released 1. https://ubuntu.com/security/CVE-2018-9860

Affected software / configurations for CVE-2018-9860

Vendor Product Version Raw CPE
botan_project botan >= 1.11.32, < 2.6.0 cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*

References for CVE-2018-9860

cvelogic Threat Intelligence