How severe is CVE-2026-25126?

CVE-2026-25126 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability none.

Is CVE-2026-25126 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25126?

CVE-2026-25126 affects Polarlearn. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-25126?

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.

Does CVE-2026-25126 have an EU (EUVD) identifier?

Yes. CVE-2026-25126 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4937.

When was CVE-2026-25126 published?

CVE-2026-25126 was published on 2026-01-29 and last updated on 2026-06-17.

CVE-2026-25126

CVE-2026-25126 is a high-severity vulnerability in Polarlearn with a CVSS 3.x base score of 7.1. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-4937
Weakness: CWE-20
Affected product: Polarlearn
Published: 2026-01-29
Last modified: 2026-06-17

Description

PolarLearn is a free and open-source learning program. Prior to version 0-PRERELEASE-15, the vote API route (`POST /api/v1/forum/vote`) trusts the JSON body’s `direction` value without runtime validation. TypeScript types are not enforced at runtime, so an attacker can send arbitrary strings (e.g., `"x"`) as `direction`. Downstream (`VoteServer`) treats any non-`"up"` and non-`null` value as a downvote and persists the invalid value in `votes_data`. This can be exploited to bypass intended business logic. Version 0-PRERELEASE-15 fixes the vulnerability.

Frequently asked questions

What is CVE-2026-25126?: PolarLearn is a free and open-source learning program. Prior to version 0-PRERELEASE-15, the vote API route (`POST /api/v1/forum/vote`) trusts the JSON body’s `direction` value without runtime validation. TypeScript types are not enforced at runtime, so an attacker can send arbitrary strings (e.g., `"x"`) as `direction`. Downstream (`VoteServer`) treats any non-`"up"` and non-`null` value as a downvote and persists the invalid value in `votes_data`. This can be exploited to bypass intended business logic. Version 0-PRERELEASE-15 fixes the vulnerability.
How severe is CVE-2026-25126?: CVE-2026-25126 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability none.
Is CVE-2026-25126 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25126?: CVE-2026-25126 affects Polarlearn. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-25126?: 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.
Does CVE-2026-25126 have an EU (EUVD) identifier?: Yes. CVE-2026-25126 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4937.
When was CVE-2026-25126 published?: CVE-2026-25126 was published on 2026-01-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:polarlearn:polarlearn:-:*:*:*:*:*:*:*

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