How severe is CVE-2018-9860?

CVE-2018-9860 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-9860 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-9860?

CVE-2018-9860 affects Botan Project Botan. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-9860?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-9860 published?

CVE-2018-9860 was published on 2018-04-12 and last updated on 2026-06-17.

CVE-2018-9860

CVE-2018-9860 is a high-severity vulnerability in Botan Project Botan with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-193.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-193
Affected product: Botan Project Botan
Published: 2018-04-12
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2018-9860?: CVE-2018-9860 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-9860 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-9860?: CVE-2018-9860 affects Botan Project Botan. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-9860?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-9860 published?: CVE-2018-9860 was published on 2018-04-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:botan_project:botan:*:*:*:*:*:*:*:*

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