Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf45441004754247…

MALICIOUS

PDF

77.8 KB Created: 2021-09-16 18:47:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e0ac0be37e802fe3a43e195ce9470e01 SHA-1: 41cafd0065419c9ce03970c0094867a560bfe807 SHA-256: cf45441004754247ed318c0826834c1256b50a82443991a4f67471c10039e6b8
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple external links, with several heuristics flagging it as a link farm on disposable hosting and containing algorithmically-generated URLs. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure and URL patterns are indicative of a common phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://crysiq.ru/uplcv?utm_term=rime+of+the+frostmaiden+dm+screen+pdf PDF link annotation
    • http://allivecoat.com/userData/board/file/bazevuderepiba.pdfIn PDF document text
    • http://hz-karavany.cz/ckfinder/userfiles/files/86051405155.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/sukiweniwe.pdfIn PDF document text
    • http://www.first-classlogistics.com/image/upload/File/26631574018.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/sodabowejunezizufuga.pdfIn PDF document text
    • http://artvideo74.ru/upfiles/files/54406918397.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/43381932992.pdfIn PDF document text
    • https://limsurdua.com/contents/files/23906735090.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/figitakawonenobaponej.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/nosifonerinoxabovizas.pdfIn PDF document text
    • http://hypotekaprezamestnancov.sk/res/file/gusedijilemetuv.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/46763689863.pdfIn PDF document text
    • https://noithathoaphat11.com/upload/files/dajonuzasuv.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/68746689115.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613284eea4cc5---61353365406.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/161392a11228d2---netumifimezevapil.pdfIn PDF document text
    • https://quanticabtl.com/cms_2018_quantica/sgi_userfiles/userfiles/files/46975592403.pdfIn PDF document text
    • http://kalkulacka-hypo.cz/userfiles/files/93756698777.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/49688915074.pdfIn PDF document text
    • https://cyberbirddog.com/userfiles/files/subeveten.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/nesutipujavo.pdfIn PDF document text
    • http://olympiad-bigben.ru/ckfinder/userfiles/files/65937834045.pdfIn PDF document text
    • http://greddy.com/admin/common/ckfinder/userfiles/File/sijegivepikol.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/korinegebazazenu.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_off0000c7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FC 18760 bytes
SHA-256: 64f54b8bbf83ed074f6cd8892bf26861bf2ce8214f128110c7b4a21e3e3959ae
font_01_sfnt_off0000f83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83A 10884 bytes
SHA-256: b2a74723952c97a4ffa45e8210fe69a37d1ef56769438a24827a6cbae9ffb6da
font_02_sfnt_off0001113c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1