01 Record
CVE-2026-26747
A Host Header Poisoning vulnerability exists in Monica 4.1.2 due to improper handling of the HTTP Host header in app/Providers/AppServiceProvider.php, combined with the default misconfiguration where
CriticalPUBLISHEDCNA: mitre
CNA base score9.1 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
02 Description
A Host Header Poisoning vulnerability exists in Monica 4.1.2 due to improper handling of the HTTP Host header in app/Providers/AppServiceProvider.php, combined with the default misconfiguration where
03 Exploitation and scoring
- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.44% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 38.3% of scored records. A rank, not a probability.
- NVD base score
- 9.1 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-02-20 00:00Z8 MO AGO
- Last updated
- 2026-02-23 20:37Z8 MO AGO
- Reserved
- 2026-02-16
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Critical (CVSS 9.1)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Weaknesses
- CWE-644Improper Neutralization of HTTP Headers for Scripting SyntaxVariant
- Data version
- 5.2
- Document digest
- db1b37cd595336587a8d96d621363c39d524318808448912b328bb3f6a3d3449
05 Affected products
VendorProductVersionsPlatforms