How severe is CVE-2021-26758?

CVE-2021-26758 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26758 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26758?

CVE-2021-26758 affects Litespeedtech Openlitespeed. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26758?

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-2021-26758 published?

CVE-2021-26758 was published on 2021-04-07 and last updated on 2026-06-17.

CVE-2021-26758

CVE-2021-26758 is a high-severity vulnerability in Litespeedtech Openlitespeed with a CVSS 3.x base score of 8.8. 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-269.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-269
Affected product: Litespeedtech Openlitespeed
Published: 2021-04-07
Last modified: 2026-06-17

Description

Privilege Escalation in LiteSpeed Technologies OpenLiteSpeed web server version 1.7.8 allows attackers to gain root terminal access and execute commands on the host system.

Frequently asked questions

What is CVE-2021-26758?: Privilege Escalation in LiteSpeed Technologies OpenLiteSpeed web server version 1.7.8 allows attackers to gain root terminal access and execute commands on the host system.
How severe is CVE-2021-26758?: CVE-2021-26758 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26758 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26758?: CVE-2021-26758 affects Litespeedtech Openlitespeed. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26758?: 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-2021-26758 published?: CVE-2021-26758 was published on 2021-04-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:litespeedtech:openlitespeed:1.7.8:*:*:*:*:*:*:*

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