Malicious PDF — malware analysis report

Static analysis result for SHA-256 813c38a3195d6765…

MALICIOUS

PDF

79.6 KB Created: 2021-09-12 15:58:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ec5fe8fa8744bcd72eb244efd1d85dcb SHA-1: 7cbb1051ffb4497c54bcd7fb18b13d4a5511e551 SHA-256: 813c38a3195d6765da0654e2e26f6aa6c18a53bafe28a79a8747ab50593d730c
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The 'SE_CALLBACK_LURE' heuristic strongly suggests a callback phishing or tech-support scam pattern, where the user is prompted to call a phone number. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a phishing or credential harvesting attempt, likely leveraging social engineering tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://crewmak.ru/uplcv?utm_term=ipad+not+receiving+sms PDF link annotation
    • http://rubivina.com/Images_upload/files/46328138215.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/kujebi.pdfIn PDF document text
    • https://newline-eg.com/userfiles/file/lofizisupe.pdfIn PDF document text
    • http://artpolyclinic.com/file/files/xakowitunotozawokedesu.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/60622444353.pdfIn PDF document text
    • http://spalovnachemolak.sk/userfiles/file/91623441512.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/xosawudavelozoxenadosax.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/tifidagivewusizabe.pdfIn PDF document text
    • http://nhasachnguyenvancu.com/Images_upload/files/58730293381.pdfIn PDF document text
    • http://ausafe.net/images/art/files/42387628820.pdfIn PDF document text
    • https://alternativecarrepair.nl/userfiles/file/65094088371.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354c7eb821b---fupusumor.pdfIn PDF document text
    • http://stonepigments.com/userfiles/file/taneb.pdfIn PDF document text
    • https://expomediainc.com/upload/file/59348290052.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/95914266393.pdfIn PDF document text
    • http://tourgrodno.by/images/content/file/sesivufijuruniv.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/vogodoxalet.pdfIn PDF document text
    • https://investir-petroleo.pt/ckfinder/userfiles/files/tujigu.pdfIn PDF document text
    • http://e2ingenieros.com/ckfinder/userfiles/files/93281446118.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/rolumelikijex.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16136e947492b3---jobigofavorilujuw.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/6600041117.pdfIn PDF document text
    • 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_off0000d09e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD09E 10828 bytes
SHA-256: 593bc3acf5ac5ff145046bdfe5ef293c33762cd3a5e69872b012f5db12c6f185
font_01_sfnt_off0000e965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE965 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010177.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10177 18708 bytes
SHA-256: 4ea7a4a53d7995894cdd6eb35425ebc98ba623db4e86ba36d8255be2abf5a01e