How severe is CVE-2018-10240?

CVE-2018-10240 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2018-10240 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-10240?

CVE-2018-10240 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-10240?

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-2018-10240 published?

CVE-2018-10240 was published on 2018-05-16 and last updated on 2026-06-17.

CVE-2018-10240

CVE-2018-10240 is a high-severity vulnerability in Solarwinds Serv-u with a CVSS 3.x base score of 7.3. 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-331.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-331
Affected product: Solarwinds Serv-u
Published: 2018-05-16
Last modified: 2026-06-17

Description

SolarWinds Serv-U MFT before 15.1.6 HFv1 assigns authenticated users a low-entropy session token that can be included in requests to the application as a URL parameter in lieu of a session cookie. This session token's value can be brute-forced by an attacker to obtain the corresponding session cookie and hijack the user's session.

Frequently asked questions

What is CVE-2018-10240?: SolarWinds Serv-U MFT before 15.1.6 HFv1 assigns authenticated users a low-entropy session token that can be included in requests to the application as a URL parameter in lieu of a session cookie. This session token's value can be brute-forced by an attacker to obtain the corresponding session cookie and hijack the user's session.
How severe is CVE-2018-10240?: CVE-2018-10240 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2018-10240 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-10240?: CVE-2018-10240 affects Solarwinds Serv-u. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-10240?: 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-2018-10240 published?: CVE-2018-10240 was published on 2018-05-16 and last updated on 2026-06-17.

References

https://www.bishopfox.com/news/2018/05/solarwinds-serv-u-managed-file-transfer-insufficient-session-id-entropy/

Affected products (1)

cpe:2.3:a:solarwinds:serv-u:*:*:*:*:*:*:*:*

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