Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5ad615e9611d998…

MALICIOUS

PDF

88.4 KB Created: 2021-09-12 08:38:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 82330004662dfcad441a5d2e7a70a681 SHA-1: e6174cf387520351d28739a59299a90c43abe79c SHA-256: b5ad615e9611d9989772c16b91fd4932f4253b7c9ccc1c639efc6b16e1b1cc40
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior as a tactic for distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 http://ridendo.cz/files/file/newokowoked.pdf In PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/gofufezijadipomiwagi.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/jirezepenasin.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/41680902600.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/70471399771.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/vojanipa.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/fezuginevoni.pdfIn PDF document text
    • http://coachhouse.info/assets/file/12548546728.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a04ca8069---38852423832.pdfIn PDF document text
    • https://jotelek.hu/files/file/50108302947.pdfIn PDF document text
    • http://innotack.com/userfiles/file/xesaf.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/dobexudiwokawa.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/votataxiruni.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/48458122799.pdfIn PDF document text
    • http://re-media.ru/foto/ck/files/82485895141.pdfIn PDF document text
    • https://oncallanatomist.com/ckfinder/userfiles/files/82658738581.pdfIn PDF document text
    • http://kcntanduc.vn/img_duhoc/files/babatagiwosakewa.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/fofafazi.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/fasirimaterusilajojosi.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/zarabitajaxukolavibuvis.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/92837876907.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/tosovo.pdfIn PDF document text
    • https://majubesar.net/contents/files/ratodebapowodekitanuriwal.pdfIn PDF document text
    • http://gurolmumcu.com/userfiles/file/2981426952.pdfIn PDF document text
    • http://hengtongrongshang.com/jingkelun/userfiles/files/20210905170138.pdfIn PDF document text
    • https://pezenasenchantee.fr/userfiles/file/26240276834.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/janoliwo.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/bixukotalafafokilup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=free+music+app+for+iphone+11PDF 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_off0000f5d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DED 10728 bytes
SHA-256: 33814bf959a0f73bdf4405b5e726ed3cfd8d60df2ef61cef9984268766a8be28
font_02_sfnt_off00012660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12660 17588 bytes
SHA-256: 49d433ec3b7609e3c23a08af6f3dbcda70fc3cc1035dd6958d8003792d0094de