Malicious PDF — malware analysis report

Static analysis result for SHA-256 494f7864cbe737e5…

MALICIOUS

PDF

77.3 KB Created: 2021-09-17 22:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 333fca762d33b2b563ad3c7735674a48 SHA-1: 18b58a3933e60bf672fcf544af5e04b45f15e717 SHA-256: 494f7864cbe737e5273cbb73f902fdaa384be789108c3e3a488b30480e1404f3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, indicating it's a phishing or trojan PDF. It contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a redirection scheme to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the final destination. No scripts were extracted, but the presence of external URIs points to a drive-by download or phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://smidgel.ru/uplcv?utm_term=555+spiritual+number+meaning PDF link annotation
    • https://brawlcall.com/ckfinder/userfiles/files/37215160846.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/95217466727.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/jatibisitepafojugututal.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/25443700525.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/tinene.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/550ebf80e20d7587cdfdca2388de7023/najumanevidanozovezanutej.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/xumazudimubumupomevejofe.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/winusodujawujax.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/41238971254.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/fexaxavaxovevoravupevux.pdfIn PDF document text
    • http://vers-ma.de/userfiles/file/gipezaroxakonosojowu.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/nizaruzow.pdfIn PDF document text
    • http://aimecostruzioni.it/userfiles/files/pasujigida.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/62974644526.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/52c892e762f17b160345260acbc7a662/gigugade.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/nodiwi.pdfIn PDF document text
    • http://tulga.ru/editor/files/72853584183.pdfIn PDF document text
    • http://pegastelco.com/pictures/files/80876128686.pdfIn PDF document text
    • http://gcoekmr.org/cukashmir/User_Files/imagefile/10319507834.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/64243938527.pdfIn PDF document text
    • http://nmways.com/uploads/fckupload/file/6224131601.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210906_AD76468AC6DC460B.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/jujalosolejudom.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_off0000c9ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EE 17800 bytes
SHA-256: d5c1e154f307c73e66f4f8299770f995a7e786ad995cd7fe65401a24bdf5ef72
font_01_sfnt_off0000f769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF769 10752 bytes
SHA-256: c397a9235ac421eefd3ba930b0ca99acbf3097e2c6a1825b8769733f843743db
font_02_sfnt_off00010fe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1