Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d8d51c039c9763c…

MALICIOUS

PDF

82.2 KB Created: 2021-09-19 15:58:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 01054044a3c8de202b0084d16c293206 SHA-1: 4273bdef2d2f0934b05249f088281d91a8186fe6 SHA-256: 5d8d51c039c9763c05f993b0a862af9ca0528cd7af83027b7facf3946208a8ba
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF contains a large number of embedded URLs pointing to various domains, suggesting a link farm or phishing campaign. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic specifically highlights the nature of these links, indicating they are likely used for SEO manipulation or to distribute malware. No scripts were extracted, but the sheer volume of external links is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://irlanc.ru/uplcv?utm_term=where+is+file+manager+app+on+android PDF link annotation
    • http://vegman-kzn.com/ckfinder/userfiles/files/37680487875.pdfIn PDF document text
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/jakogipivugewomezaxugebam.pdfIn PDF document text
    • https://plantbiochem.com/ckfinder/userfiles/files/lijejafipagem.pdfIn PDF document text
    • http://najlepsietorty.sk/uploads/fck/file/kisipibomomet.pdfIn PDF document text
    • http://xn----8sbfhu6ab4bqv.xn--p1ai/userfiles/file/21225300712.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/74764493657.pdfIn PDF document text
    • http://beijingxinzhi.com/userfiles/file/20210903100555_1816529891.pdfIn PDF document text
    • http://ailizia.com/userfiles/tabedasopakodisepejufum.pdfIn PDF document text
    • http://195exim.com/datas/files/38145172097.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145f67e5dd55---mowogef.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/kixobaxuz.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/8767020331.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/xivadodajujifap.pdfIn PDF document text
    • http://hanabi-la.com/uploads/files/51613326698.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/kewaterewik.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/xitisuzupes.pdfIn PDF document text
    • http://ayrh.internet-match.com/upload/files/19124862604.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/d67d28ce88199ae32139eaaa86a76b55/53762679067.pdfIn PDF document text
    • https://oferta.lt/i/File/35842821124.pdfIn PDF document text
    • http://schokozentrale.de/idata/digitojifer.pdfIn PDF document text
    • http://ysenb.kr/board/file/editor/file/paxejuputazizoporosoge.pdfIn PDF document text
    • http://maurovalleferroarchitetto.eu/userfiles/files/76667055277.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/gimatoxatakudipajinur.pdfIn PDF document text
    • http://wirtrauenuns.ch/images/file/xevirupadan.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/93074452659.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_off0000dd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7D 10840 bytes
SHA-256: e588c02d062bbea67400d03c1c7234ec1a9c4a3244479e9ef2fd73657f815a14
font_01_sfnt_off0000f612.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF612 17436 bytes
SHA-256: 9872a11cadc6a2310f071b4eebe90744b4957daea048fa4557d87524c1dcb3b9
font_02_sfnt_off00012300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12300 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1