Malicious PDF — malware analysis report

Static analysis result for SHA-256 55da9a3862835ae5…

MALICIOUS

PDF

75.1 KB Created: 2021-09-05 23:29:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d9afd6b121e7abb1b3ff30afef7e9440 SHA-1: 7b2cc922f69ca88ab5dcc9f77303802366fc664a SHA-256: 55da9a3862835ae55459cb0565139232471b99b9cdb59f7526e8432d46993d4d
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains numerous links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The presence of multiple external URIs and link farms indicates an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc8af54d22---22216943301.pdf In PDF document text
    • http://itkaufmann.com/images/fckimages/file/jaxasu.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb5f756cd7---4616046994.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160ce8459a661d---66191165060.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/mevuvipapojoneb.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/32434684351.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160cba16255d37---dazunatujodazexetifex.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/atjoiluqirt28bvde1h5f5cd71/15882510575.pdfIn PDF document text
    • https://ibrahimkoc.com/images/Media/files/63737730211.pdfIn PDF document text
    • http://stepsforstarlight.com/clients/c/c6/c668404594a1c08d975ab50c7bec58f6/File/teguvegifi.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dac31abbbb---wozoxow.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/wamanemovaraxuvovaw.pdfIn PDF document text
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/7agg2qirk7ilupm0e9t9mb0fe0/88322063425.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/zuxod.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/b0uueit7hiaaet6v68e8tc2tm1/bapatebamolobozena.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/kefomesuvorevimutodutero.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608734959ead8---37910522680.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/b22ae2b8d06343efeac2a4a4638afc73/69793649906.pdfIn PDF document text
    • http://domplus.su/userfiles/files/rivevevudatanat.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/muwowiwimosesikenu.pdfIn PDF document text
    • http://brooklynsmokeshops.com/admin/images/file/mapikavesanola.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/8070196634.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/l38hm0gmq7d2o3u5vap1if5osm/dopagulefexivajola.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff31d8a772b---82067994906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=check+spelling+in+pdf+onlinePDF 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_off0000c689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC689 10664 bytes
SHA-256: 00dd2830369b82b504e282e4d7bb2777828883e876f2fbd9e369278a7ed60e42
font_01_sfnt_off0000deb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C4 15792 bytes
SHA-256: d97c544f76d5787765afd2403c63688f705563db1d1c24e264353f56e1acd161