Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b51eb3b847bdac…

MALICIOUS

PDF

81.1 KB Created: 2021-09-17 14:27:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f481cf254bf9c6cae655fde0f3eb265b SHA-1: a0eaf2c26a19fcdf9b41610e375ffb2778e6b6db SHA-256: 37b51eb3b847bdacfa3b5a82191337b955759e982527540309b1bac9b0216620
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an intent to redirect users to malicious sites. The embedded URLs, such as those hosted on `brylka-kfz.de` and `greshamgilessalon.com`, are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/c380c6ce8fc3866880de0887e5a6fda7/64947296405.pdf In PDF document text
    • http://naturalmis.com/userfiles/file/ledosifirunuvid.pdfIn PDF document text
    • https://anukulagrotech.com/ci/userfiles/files/32859180195.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132e9f6ed0df---juvoliwixutofajo.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/85038642148.pdfIn PDF document text
    • https://banderlogclub.ru/Files/file/jajutosekegonoxagizenixo.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/99121780331.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/maworikunuf.pdfIn PDF document text
    • http://yasairamenbar.com/uploads/files/41067670676.pdfIn PDF document text
    • http://clinical-pain.com/pds/userfiles/files/2396583745.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/23781993671.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/31389507331.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210916_044309.pdfIn PDF document text
    • http://exms.fr/sites/default/files/file/87117591468.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/puvaxik.pdfIn PDF document text
    • https://ottopianos.nl/files/15711840530.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/fumatolagowovaku.pdfIn PDF document text
    • http://robbes.nl/media/files/78022537874.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/gururupuveninonefopupi.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/sezakolegobebanuru.pdfIn PDF document text
    • http://dieterheich.de/images/uploads/file/vamewobewukoken.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/tixetux.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/44925286654.pdfIn PDF document text
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/56447338677.pdfIn PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/22760100494.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=stream+polar+expressPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD675 10392 bytes
SHA-256: 56b7ee1c7ef317b7be655901beb01df2d33e079c08c1e451744f6dfde2f5f182
font_01_sfnt_off0000ee0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001061d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1061D 18324 bytes
SHA-256: da2ac751a00c4ee4ed40fabff7e46051d4fd1cecc4501741bbeda9b70ad79fe7