Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc77a551699ce422…

MALICIOUS

PDF

80.6 KB Created: 2021-09-06 08:52:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6402b3705d12d66d75cb043724066929 SHA-1: e8071afc47fc6264e99866d500466582ba57d928 SHA-256: bc77a551699ce42257ed895e86e6a0c075bf35f230caaf60fc6fa95e33d3eb69
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially compromised or disposable domains. The presence of multiple external URIs and link farm indicators suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://queure.ru/uplcv?utm_term=halimbawa+ng+replektibong+sanaysay+pdf PDF link annotation
    • http://ctkupavna.ru/upload/file/jirotilitefu.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/kizip.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/tegunumukeruta.pdfIn PDF document text
    • http://kcde.kr/userfiles/file/27537517983.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/16208211056119d536e5cd5.pdfIn PDF document text
    • http://badgerhillfarm.uk/pebodaxolinusofaxu.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1608af6d108d2a---99675369839.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/gawavisijalaneradibe.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/47908254247.pdfIn PDF document text
    • http://frickcontrols.com/uploads/files/mugowiwifapetaxedepux.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/34d2d169e0d48d68a3e43f8c4b2584fe/maviwozesukogepinat.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d75447dfd---81838478862.pdfIn PDF document text
    • http://ya-ke.cn/admin/upload/somikopefizozeguva.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/28400960087.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/hlar5iihts7qc54eg2e73bgm9i/veveriwom.pdfIn PDF document text
    • http://dr-temt.ru/images/file/10155166713.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/robejavi.pdfIn PDF document text
    • https://kaplaitalia.it/userfiles/files/jutusalawaniwobuba.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16093a57a628f6---pajop.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/246fb4e3e42c4a5567e4ba614ffcc664/14555117844.pdfIn PDF document text
    • http://tochalco.com/uploads/files/49261748848.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/besalo.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/56683435944.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd7a6f8aba3---58826140019.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_off0000da6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA6E 11264 bytes
SHA-256: 6f8334736f7712f4facf0a715aac36a6a445527564e8c7828bbd629fbce170b2
font_01_sfnt_off0000f46e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF46E 15596 bytes
SHA-256: 9a7abf38b469d85515aad2efbcc71bf6757278d4f2ec6c3fc69cbbcfb58f0dfc
font_02_sfnt_off00011c89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1