Malicious PDF — malware analysis report

Static analysis result for SHA-256 71dd5a195587dfde…

MALICIOUS

PDF

70.3 KB Created: 2021-09-30 20:17:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5ed641ffbd9ab3279376159f045ed091 SHA-1: 4a11c1f0b816b66a87771b89cf890ceff8b41ada SHA-256: 71dd5a195587dfde7747a7b10e69c3e720600e2657d8d11548baf200a3050b34
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The sample is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm and contains a callback lure, prompting users to call a phone number for issues like billing or refunds. While no scripts were extracted, the document's structure and heuristic firings strongly suggest a phishing or scam attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://menokatea.com/ckfinder/userfiles/files/74563467609.pdf In PDF document text
    • http://canoto.us/Images_upload/files/81694166847.pdfIn PDF document text
    • http://bebsulmare.com/userfiles/files/viwexutosawibobuf.pdfIn PDF document text
    • http://inlovehuahin.com/file_media/file_image/file/tuwaxurisaxejurup.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/xojebasul.pdfIn PDF document text
    • https://singhaniabrothersltd.com/ckeditor/ckfinder/userfiles/files/lowarabusibunebore.pdfIn PDF document text
    • http://gzbaosui.com/uploadfile/files/pubozuvuvared.pdfIn PDF document text
    • http://hasadtemizlik.com/upload/file/69360780025.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/60471072631.pdfIn PDF document text
    • https://banghenails.com/upload/file/luxibivuzuxesuparun.pdfIn PDF document text
    • http://tarnava.eu/user_images/file/jifoja.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/kalupimamatamanazosu.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/50828810085.pdfIn PDF document text
    • https://tkbhanna.com/ckfinder/userfiles/files/91755431624.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614acbcc43586---girewudabawaw.pdfIn PDF document text
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/43614986479.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/tizixe.pdfIn PDF document text
    • http://www.farnostbobrova.cz/ckfinder/files/mowilu.pdfIn PDF document text
    • http://ibarugi.com/fckeditor/userfiles/file/supawawigebodiku.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/9407273441.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/fosiziwobisanu.pdfIn PDF document text
    • http://bdn10.cz/files/file/julam.pdfIn PDF document text
    • https://kultmotor.hu/images/files/vekufofumoxupozavekovixa.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210914182407.pdfIn PDF document text
    • https://denizlihorozu.com/resimler/files/nigitaduzufulujulutut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=voice+based+email+for+blind+project+in+androidPDF 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_off0000b34a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB34A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB5C 15072 bytes
SHA-256: 031d37f978876e0b0ae29f5389e7a0c8b48f5a7cb0dfb8b136a24820ca5066c0
font_02_sfnt_off0000f199.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF199 11020 bytes
SHA-256: 85be7cde6fd5211014cbd0784e6f8461ea3be8237b07e83178d395cc5ff2d6d7