Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5afffec1824699f…

MALICIOUS

PDF

67.4 KB Created: 2021-09-19 05:25:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e51b8e1c10565cc924e6b74f477531db SHA-1: 5c121a8766151eb5539946cf6aeb6f561fa41cea SHA-256: c5afffec1824699fdf69ff393046f054ada8ecc932b41120b557e2efa4f3c49a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. The presence of embedded URLs and the nature of the link farm suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://huntic.ru/uplcv?utm_term=free+sms+side PDF link annotation
    • https://rarahil.org.np/ckfinder/userfiles/files/49863112452.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/mke75jq9386rm7br7s5hrgf093/lupefijupibafonurigubaviv.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/jimidodosen.pdfIn PDF document text
    • http://rayanchem.com/d/files/titepepaka.pdfIn PDF document text
    • https://wegofa.com/userfiles/file/99036998344.pdfIn PDF document text
    • https://ihotel2b.com/upfiles/editor/files/84079080283.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/vajerotefu.pdfIn PDF document text
    • http://thuaphatlailongthanh.vn/upload/contentFile/minhchau/file/66540871708.pdfIn PDF document text
    • http://dogoducthien.com/uploads/files/4070634131.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/73827069263.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zavave.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/jefunawamoxitekesekepex.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/un88cdl1trc8v0co1a43msvu15/37677299806.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/25821276591.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/risexu.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/17260454055.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/lanaruridujererefunem.pdfIn PDF document text
    • http://inannamsao.com/uploads/files/91550730485.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/wopede.pdfIn PDF document text
    • http://mishor-uvk.com/uploads/files/16903779797.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/naxoberigale.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613db539330eb---64500360240.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_off0000ad4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD4F 9856 bytes
SHA-256: c555be35b30fe0f1101e6436c8b790aa8309b5aaf33373ffffc51f092f6a1280
font_01_sfnt_off0000c2ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2ED 15020 bytes
SHA-256: 8946037a32a952f6ecfc85ef18cdb62ec1153b994e4902c00fc0a181acab7b62
font_02_sfnt_off0000e877.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE877 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1