Malicious PDF — malware analysis report

Static analysis result for SHA-256 27f79e19d636a49d…

MALICIOUS

PDF

92.8 KB Created: 2021-07-03 01:45:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 87eea0772819a5410791dbe4f121c999 SHA-1: 37aabdf3426a63d775b090661cad9e6542788a89 SHA-256: 27f79e19d636a49d7c8ef766189abd38de2023b119a635526e4581f9032fc6a6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, but the presence of external URIs and the link farm heuristics strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

Heuristics 6

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=i+woke+up+sweating+in+the+middle+of+the+night PDF link annotation
    • https://majubesar.info/contents//files/tisaxidetofiviludazetuw.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160983a42cf428---gukexidenirefigozarajiwow.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/656457473.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16095557c253bd---memavisagavawijola.pdfIn PDF document text
    • https://avenue102.com/uploads/file/98770709826.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/32259977444.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/newoxedimemofira.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/liriwimonopa.pdfIn PDF document text
    • http://laweasy.kr/userfiles/file/lotunodasejotanu.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef82339b26---kabopuwanasasiwutupivum.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16071a2e6ae861---95417966927.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/d42k6ti78bv70eb92j1m2fanai/38128787138.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/b53fd01e1975c649d6ae0da1dc0c7e3f/81783341433.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf1855781db---xovik.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16084f6fcb18e5---pujepesizavakise.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/fimotutuwifutug.pdfIn PDF document text
    • http://111-orte.de/testarea/cwsCMSlight/media/files/gezuxokelotakut.pdfIn PDF document text
    • http://wurbs-hanau.de/userfiles/file/jigabexonifuxexitiguziko.pdfIn PDF document text
    • http://thietbixanh.net/uploads/files/36654656828.pdfIn PDF document text
    • https://paron-rebondir.com/uploads/files/rosezevutasavejax.pdfIn PDF document text
    • http://lhsclassof1971.com/clients/74120/File/dopaforaguxowomelabixaguw.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/rinatizubije.pdfIn PDF document text
    • http://sowitech.vn/upload/files/97589278238.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eedb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDB 16448 bytes
SHA-256: 0e4cde3d5bdd5452960de995a4807c8da4ec665155a9812e2f8e54e6c49b7878
font_01_sfnt_off000105b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B0 16848 bytes
SHA-256: 28f188cb0bc08bcbe12fc157e9b22cfb25aa429917fc787c6dba2001d04ac39c
font_02_sfnt_off00013190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13190 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000149a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149A7 11076 bytes
SHA-256: ccca36b9ea7823a2e6de5b676373e67d736b45a1fb9a5667cf3694ad614eab9d