Malicious PDF — malware analysis report

Static analysis result for SHA-256 18651504abccb49d…

MALICIOUS

PDF

87.0 KB Created: 2021-08-27 08:07:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7ed718f9d2b579e7f2765a0340dd07a3 SHA-1: 905fcdc44238f5711e25e82137ccd83b031d71c9 SHA-256: 18651504abccb49df14bd2586e1359e34f535b56d5867b485251e45a1d13252b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with a high confidence score. It functions as a link farm, containing numerous URLs pointing to potentially compromised WordPress sites and other disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a network of links, likely for SEO manipulation or to host phishing/malware content. While no scripts were extracted, the presence of multiple links to potentially compromised upload directories suggests a distribution or redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9904

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
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074ade17fcc5---30155435287.pdf In PDF document text
    • http://www.medicellbank.com/userfiles/files/13675653953.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/gigewesiboderevuzelete.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/a4213e01ac55c48299241b6ebe80374a/vopuputejiteso.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/165faa94feb90e9be2de4f2e8f8809c4/gabidogorer.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/koriwajumin.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/24d222cbcd45e62b6dbd6fbde1e2632f/fujesaz.pdfIn PDF document text
    • http://tecksco.com/upload/files/65220164136.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607502cf4d588---gezegufu.pdfIn PDF document text
    • http://splogservice.ru/content/files/zefuru.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16093d185cdbc2---puwanikisab.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/u0vbl17rppag1gavt76hgils95/89415516645.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/muburilodudalijetewogor.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16103068cc625f---25141838939.pdfIn PDF document text
    • http://lovemyskindayspa.com/clients/d/d9/d99ed7cf7cbac978b7326c22a81d1608/File/25508462988.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/saweri.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/lokisusoxubet.pdfIn PDF document text
    • https://monyetjoget.com/contents//files/gukotodutopijerepefu.pdfIn PDF document text
    • http://prosquash.by/data/vulapimiteporoz.pdfIn PDF document text
    • http://qlinairnv.be/userfiles/file/befajopifukowopirezil.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/tudojesafetos.pdfIn PDF document text
    • https://pubs-icfas.org/icfas_new/dev/ckfinder/userfiles/files/mojiginofotidefasofemul.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16072ab5f040ee---vufewurifobu.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/sadipadilotan.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/kaduwidozi.pdfIn PDF document text
    • http://studiotecnicopinto.it/userfiles/files/ruloxokukarajaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=how+to+get+rid+of+flabby+chestPDF 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_off0000eff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10808 10980 bytes
SHA-256: 77ae4fba551b2b12e258c0f9954b0b3c62050725280349c545735bbaa07da976
font_02_sfnt_off0001217b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217B 16884 bytes
SHA-256: 771e15134dbd1a9d243e87a5c988e0da1e83a5d724e3b40f59241d96d15d1b33