Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc18b7c4a36a9cdf…

MALICIOUS

PDF

83.6 KB Created: 2021-08-20 04:26:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3f03bedf384f0740f392d13691dd0b83 SHA-1: 8fbcc7942baffb5d5d9171f1d8bb87900c456372 SHA-256: fc18b7c4a36a9cdf3d597e7ebdaccd894732be84be24da3ec3cd09c1b2645f2e
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised WordPress sites and IP addresses, suggesting a link farm designed to redirect users. The presence of these links and the PDF structure strongly suggest a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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 https://medvor.ru/uplcv?utm_term=libro+de+geograf%C3%ADa+1+de+secundaria+2020+contestado+castillo PDF link annotation
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608872f8d147e---89533095262.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6264886ff---wafeso.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/68072322873.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610385db2aef4---zorepazibaguwa.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/160a8bf737892d---4348762082.pdfPDF link annotation
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160814c15128b0---81600960537.pdfIn PDF document text
    • http://isvpro.com/custom/files/geruzejiwegipakomujaj.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/sosat.pdfIn PDF document text
    • http://solee56.com/ckfinder/userfiles/files/8308973830.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca1176d43e---76490326044.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/begurokif.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072dda390bea---mutibitowod.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/nemamoruvixavoma.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160939f19805b8---gomexuremam.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160712cc9667b9---64886247461.pdfIn PDF document text
    • http://flightshop.jp/images/blog//file/9819143127.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/inf1uur6b0rn8f7emise4h8fab/taginodem.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/3f81c8b1f4aa4c681e0db873446c894c/56462424898.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/b1e6qrehnunn8k6gsbt0h6qca1/bowinesuzabe.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/xisovol.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/fdd7e5833bb80eecac8b59283660096b/bavaliga.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160842d735ab12---99264066364.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/00a02b48cf671124efa27179f9baa212/70962666822.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1607533691768f---2270396551.pdfIn PDF document text
    • https://acryl-bg.com/userfiles/file/72228203773.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_off0000dfab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAB 16916 bytes
SHA-256: 229e6185a921e77239396b04562acba6cc9b00b7da51573e45d0e005c842ddcd
font_01_sfnt_off00010a30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12247 11204 bytes
SHA-256: 841ba109394d61ecfc02a0890c9f2c385706fb7bb023e79bcc4820857c4a6b08