How severe is CVE-2026-25923?

CVE-2026-25923 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2026-25923 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-25923?

CVE-2026-25923 affects Mylittleforum My Little Forum. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-25923?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-25923 have an EU (EUVD) identifier?

Yes. CVE-2026-25923 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-6251.

When was CVE-2026-25923 published?

CVE-2026-25923 was published on 2026-02-09 and last updated on 2026-06-17.

CVE-2026-25923

CVE-2026-25923 is a critical-severity vulnerability in Mylittleforum My Little Forum with a CVSS 3.x base score of 9.1. 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-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v4: 8.7
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-6251
Weakness: CWE-434
Affected product: Mylittleforum My Little Forum
Published: 2026-02-09
Last modified: 2026-06-17

Description

my little forum is a PHP and MySQL based internet forum that displays the messages in classical threaded view. Prior to 20260208.1, the application fails to filter the phar:// protocol in URL validation, allowing attackers to upload a malicious Phar Polyglot file (disguised as JPEG) via the image upload feature, trigger Phar deserialization through BBCode [img] tag processing, and exploit Smarty 4.1.0 POP chain to achieve arbitrary file deletion. This vulnerability is fixed in 20260208.1.

Frequently asked questions

What is CVE-2026-25923?: my little forum is a PHP and MySQL based internet forum that displays the messages in classical threaded view. Prior to 20260208.1, the application fails to filter the phar:// protocol in URL validation, allowing attackers to upload a malicious Phar Polyglot file (disguised as JPEG) via the image upload feature, trigger Phar deserialization through BBCode [img] tag processing, and exploit Smarty 4.1.0 POP chain to achieve arbitrary file deletion. This vulnerability is fixed in 20260208.1.
How severe is CVE-2026-25923?: CVE-2026-25923 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2026-25923 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-25923?: CVE-2026-25923 affects Mylittleforum My Little Forum. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-25923?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-25923 have an EU (EUVD) identifier?: Yes. CVE-2026-25923 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-6251.
When was CVE-2026-25923 published?: CVE-2026-25923 was published on 2026-02-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mylittleforum:my_little_forum:*:*:*:*:*:*:*:*

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