Malicious PDF — malware analysis report

Static analysis result for SHA-256 c86db79ac7099093…

MALICIOUS

PDF

83.8 KB Created: 2021-09-07 10:58:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 411eec0534aba06fda462d93e0c2a0e7 SHA-1: dc47103e4a4b6c446b92fefc35ad59060d86452d SHA-256: c86db79ac7099093a9c177fec82f9ee9ce4993edbf1b14f208b35a55a59eaf2c
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and ML classifiers indicated high maliciousness. Heuristics identified it as a link farm, with many distinct hosts, suggesting a phishing or SEO manipulation scheme. The document body is heavily obfuscated and unreadable, but the presence of numerous URLs pointing to potentially compromised CMS uploads and disposable hosting reinforces the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://drivescuolaguida.it/userfiles/files/54753975058.pdf In PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/849a34e0d0cd57a96aadc2f94636a91a/83625646698.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/rulukodudopozobitabezusu.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-06-25-00-21-05-UzCWL3OO.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/dojaviguniwumewuduxe.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/665238ca45d2ad9504d9af16b04fcdfa/varolukanekubodibesuzulu.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/fusuladaterem.pdfIn PDF document text
    • https://blueridgelightingandcontrols.com/wp-content/plugins/super-forms/uploads/php/files/4a86969df71a5b73f13d0cf024f170b6/20274055905.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/4013d47196a9ac1fa0c87dcd1dda7950/1394349045.pdfIn PDF document text
    • http://ximangsongthao.com/app/webroot/uploads/files/31590777315.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3944e9145---23710411045.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160adb6e1c42d0---kajejobisifiv.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/rewewuwifoxapob.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a878909deda---lorame.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/62945018632.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/dizifupojuxununadak.pdfIn PDF document text
    • http://shs1977reunion.com/clients/41590/File/pegixekemobobesuwomoxaz.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/raxozafetalutixujajokosa.pdfIn PDF document text
    • http://ducthanggroup.com/webroot/img/files/wamewabarajodif.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/gasojab.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16129d280033f6---pinolarubenoxiji.pdfIn PDF document text
    • http://debnine.net/UserFiles/File/jatamamax.pdfIn PDF document text
    • http://hornets88.com/clients/56662/File/tetogizisep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=plotting+straight+line+graphs+worksheet+ks3PDF 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_off0000e0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f8dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DC 10884 bytes
SHA-256: 77c00f2ca3a315c4833d7a4d39ff5581f868128e5b4234b632532e1dd8cabe8a
font_02_sfnt_off00011213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11213 18208 bytes
SHA-256: eaa0d3bf3dc9d5f4366574dce000eec53f39f6cb32ba7e7e283403144e04f6b1