Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3f567b615ce8602…

MALICIOUS

PDF

73.4 KB Created: 2021-09-01 21:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 55ef5e51537d5bfcc3faa0bbfc1028b6 SHA-1: 7561d26a1fc74191f07dcb40caa74113f9be207c SHA-256: d3f567b615ce8602eb5af05888bb11689cf753f9798382c019eaf50bae17a9ff
164 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of multiple heuristics related to PDF link farms and compromised CMS uploads, along with a 'download button' lure, suggests a phishing or social engineering attack. The embedded URLs point to potentially compromised or disposable hosting, further supporting this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=naa+istam+book+part+2+pdf+download PDF link annotation
    • https://aulacvn.com/upload/fck/file/61906937511.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe822c72ee---xaregadeduna.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087600b13247---zopamojazitipidoramipide.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/34360213980.pdfIn PDF document text
    • http://obrienbuilders.com/userfiles/file/34345486934.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/p1sd9vfgaon39g5sanervopoh8/82127952327.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160984c5d2926e---zadoremabe.pdfIn PDF document text
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160ff873c7fad0---guzilupaxetamemaxi.pdfIn PDF document text
    • https://lukili.ch/UserFiles/files/teketebe.pdfIn PDF document text
    • http://escrima-rlp.de/userfiles/file/serot.pdfIn PDF document text
    • http://fotosvatba.net/userfiles/file/tudesigodigixiz.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/file/sosawezatuwe.pdfIn PDF document text
    • http://babamoleskine.com/files/file/123622922.pdfIn PDF document text
    • http://johncarroll1967.com/clients/1/18/1896e795ecc2602204d707ec4e69586f/File/97777382433.pdfIn PDF document text
    • http://katachizu.com/img/news/files/dimumavifoxoti.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/31ef33ef2a1bbfbe156400ca9d742366/newanudif.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/17929377010.pdfIn PDF document text
    • http://sampsonancestry.com/clients/d/d9/d9bd9208c4e45de01aa31840e3a8c66b/File/gexijesapibimatofe.pdfIn PDF document text
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/mevar.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/26261700707.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/27493662675.pdfIn PDF document text
    • http://lachina.cn/upload/file/zipavasatawedetukejegerol.pdfIn 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_off0000c072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC072 17368 bytes
SHA-256: d9acb3050bc4e550f7f91a1cae22022209b6a38d93f421954831461168497219
font_01_sfnt_off0000ed6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10584 10940 bytes
SHA-256: 52457276ecfb4eb71dd5118448179180cd0e69079ad2f4a599c6766d8b1fa986