How severe is CVE-2021-33256?

CVE-2021-33256 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33256 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 79% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33256?

CVE-2021-33256 affects Zohocorp Manageengine Adselfservice Plus. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33256?

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-2021-33256 published?

CVE-2021-33256 was published on 2021-08-09 and last updated on 2026-06-17.

CVE-2021-33256

CVE-2021-33256 is a high-severity vulnerability in Zohocorp Manageengine Adselfservice Plus with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 79% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-1236.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.3
EPSS exploit prediction: 79% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1236
Affected product: Zohocorp Manageengine Adselfservice Plus
Published: 2021-08-09
Last modified: 2026-06-17

Description

A CSV injection vulnerability on the login panel of ManageEngine ADSelfService Plus Version: 6.1 Build No: 6101 can be exploited by an unauthenticated user. The j_username parameter seems to be vulnerable and a reverse shell could be obtained if a privileged user exports "User Attempts Audit Report" as CSV file. Note: The vendor disputes this vulnerability, claiming "This is not a valid vulnerability in our ADSSP product. We don't see this as a security issue at our side.

Frequently asked questions

What is CVE-2021-33256?: A CSV injection vulnerability on the login panel of ManageEngine ADSelfService Plus Version: 6.1 Build No: 6101 can be exploited by an unauthenticated user. The j_username parameter seems to be vulnerable and a reverse shell could be obtained if a privileged user exports "User Attempts Audit Report" as CSV file. Note: The vendor disputes this vulnerability, claiming "This is not a valid vulnerability in our ADSSP product. We don't see this as a security issue at our side.
How severe is CVE-2021-33256?: CVE-2021-33256 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33256 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 79% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33256?: CVE-2021-33256 affects Zohocorp Manageengine Adselfservice Plus. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33256?: 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-2021-33256 published?: CVE-2021-33256 was published on 2021-08-09 and last updated on 2026-06-17.

References

https://docs.unsafe-inline.com/0day/manageengine-adselfservice-plus-6.1-csv-injection

Affected products (1)

cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6101:*:*:*:*:*:*

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