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CVE-2026-128021 FrankenPHP before 1.13.2 Information Disclosure via libxml Error State in Worker Mode

6.3 mediumEPSS 0.3%

Medium (6.3) in php frankenphp. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.

On this page
FrankenPHP before 1.13.2 contains an information disclosure vulnerability that allows later clients to read earlier clients' libxml errors because worker mode never resets LIBXML(error_list) between requests. Attackers sending requests to the same worker thread can call libxml_get_errors() or libxml_get_last_error() to obtain other clients' parsed-document fragments and server filesystem paths.

Severity

CVSS 4.0

6.3 medium
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

3.7 low
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS
0.3% estimated probability of exploitation activity in the next 30 days; 23rd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: PoC · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
OWASP Top 10
A01:2025 Broken Access Control
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Deferred: the NVD does not plan to analyze it
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
php frankenphpbefore 1.13.2

Attack patterns (CAPEC)

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-200 (59).

History

  1. The NVD deferred its analysis

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

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