Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b18b5dcc5964df8…

MALICIOUS

PDF

72.5 KB Created: 2021-09-05 23:16:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c4a6e423ada82544467a33dc24ffc095 SHA-1: e04d08c9bdc623188b251a14826a20cc95fe745a SHA-256: 4b18b5dcc5964df8ee3c4474ea2c34e88a73c2f5cabf3a751e61635ed67da990
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a link farm pointing to numerous domains, many of which appear to be compromised or disposable hosting, suggesting an attempt to obscure the final destination or leverage SEO tactics for distribution. The primary goal appears to be redirecting users through these links, potentially to download further malware or engage in phishing.

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://laptopcuhaiphong.vn/upload/files/75085162807.pdf In PDF document text
    • http://xn--j1aii.su/userfiles/file/taxaxapadisamojigefaluze.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/4a98fbad88b26292300e859ad9102e12/tugefuwaziwawitinek.pdfIn PDF document text
    • http://score1forspencer.com/clients/4/45/4587145e2679cb7673d0e21b436e5c25/File/90237706843.pdfIn PDF document text
    • https://digireg.pl/upload/noribu.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/19965782252.pdfIn PDF document text
    • http://melabo.com/upload/files/67727530602.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/edb70e149977c237692e4c6f7ef4da74/kowidipidituvulokabaxowav.pdfIn PDF document text
    • http://elitvorota.ru/f/file/4439689237.pdfIn PDF document text
    • http://cuanhuadanang.vn/uploads/image/files/virefok.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/tusufemedajeduzijodumo.pdfIn PDF document text
    • http://www.520amis.com/upload/files/64729997794.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610c565181f40---nexixirisepepo.pdfIn PDF document text
    • http://liberty67.com/clients/41815/File/buwuwuxuluwowazil.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/affb17cef347b42cbc69fbff136ab5b0/37395548715.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/41d8c16e5f57244769fb47510e85adad/50413561421.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/29871329775.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/23940055675.pdfIn PDF document text
    • http://zovsh.com/Uploadfiles/files/bijoz.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/53078477139.pdfIn PDF document text
    • http://csc0311.com/userfiles/file/20210805044747_vyvca6.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/besofedokozoj.pdfIn PDF document text
    • http://yesilderecine.com/admin/editor_resim/file/502018795.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=reliance+general+insurance+form+pdfPDF 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_off0000bc31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC31 15544 bytes
SHA-256: c5aa3ad4d16a3c4496486a1961024a2b798c72d19d8ab2c45abf4fef7230a9db
font_01_sfnt_off0000e354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE354 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB6B 11012 bytes
SHA-256: 3b2ab4a12ea30ce3d9eefc8504aa30fe0627865409f228dce07318f186db8b16