How severe is CVE-2021-29487?

CVE-2021-29487 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-29487 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29487?

CVE-2021-29487 affects Octobercms October. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29487?

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-2021-29487 published?

CVE-2021-29487 was published on 2021-08-26 and last updated on 2026-06-17.

CVE-2021-29487

CVE-2021-29487 is a high-severity vulnerability in Octobercms October with a CVSS 3.x base score of 7.4. 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-287.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 5.8
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Octobercms October
Published: 2021-08-26
Last modified: 2026-06-17

Description

octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.

Frequently asked questions

What is CVE-2021-29487?: octobercms in a CMS platform based on the Laravel PHP Framework. In affected versions of the october/system package an attacker can exploit this vulnerability to bypass authentication and takeover of and user account on an October CMS server. The vulnerability is exploitable by unauthenticated users via a specially crafted request. This only affects frontend users and the attacker must obtain a Laravel secret key for cookie encryption and signing in order to exploit this vulnerability. The issue has been patched in Build 472 and v1.1.5.
How severe is CVE-2021-29487?: CVE-2021-29487 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-29487 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29487?: CVE-2021-29487 affects Octobercms October. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29487?: 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-2021-29487 published?: CVE-2021-29487 was published on 2021-08-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:*

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