Malicious PDF — malware analysis report

Static analysis result for SHA-256 857ed56d63b6a3c2…

MALICIOUS

PDF

113.4 KB Created: 2021-09-09 16:04:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: e482f7274910f9c3b0f76e2bf37eced3 SHA-1: 41be00e188e9803eb86516cdf13e23ca85ce44fe SHA-256: 857ed56d63b6a3c2a5c2f2c5c6b84977cb23cf6cde4db0ff0c906f1e90661d82
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, but the structure and URL analysis are sufficient for a high-confidence assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://chcial.ru/uplcv?utm_term=principles+of+self+defense+jeff+cooper+pdf PDF link annotation
    • http://loaamtran.com/files/usersfiles/files/kafupugus.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/galakezaz.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/f39f40839245e31558555f47a0cadfe4/nuvaziditologapigasevaga.pdfIn PDF document text
    • https://hoongnau.com/upload/files/vulodojizuxoruwi.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/02b78ac19afb442f2d3a8c5b7ca68118/vemes.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/gonirunugidurabemirim.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/3529884062.pdfIn PDF document text
    • https://www.institutvzdelavani.cz/files/fijifude.pdfIn PDF document text
    • http://denprokhorov.ru/images/file/laroligigekisipem.pdfIn PDF document text
    • https://pacie.vn/web/uploads/files/lasulekijajopowika.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/bugamuzebesigiwowiwa.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/c51285c9390f7d2792976ccf687db5bb/56084333728.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/d2bedec502f551e4d7938ebf2b7e8bbf/77072149194.pdfIn PDF document text
    • https://campermagazine.tv/public/file/vozetapixubo.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/gukejeg.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/48814036378.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132dfbe7ba05---20892953322.pdfIn PDF document text
    • https://xn--psg-9lac.hu/files/files/tidiwodivesamife.pdfIn PDF document text
    • http://kerama.altrodesign.eu/ckfinder/userfiles/files/62007659864.pdfIn PDF document text
    • http://ana-jsc.com/upload/files/75996800752.pdfIn PDF document text
    • http://kimandyoo.com/userfiles/file/majebojanudokixopegumesag.pdfIn PDF document text
    • http://wellgroup.cz/UserFiles/File/23652846557.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/xekibo.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_off00015449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15449 10484 bytes
SHA-256: f68bfd926638a29e002fd212fb855290b7c42497430eadf53b11645067a249e8
font_01_sfnt_off00016c17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18429 19692 bytes
SHA-256: 5d8708d47bf044b71cbf4dc8a5803a9550b3804a9b5e56d5b02f9a3602a9d2cc