Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5a9ae1a330a3dd1…

MALICIOUS

PDF

92.3 KB Created: 2021-09-10 04:34:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3d34a4d7f9d4234fe0a9957531659e80 SHA-1: 247ab83fbd3acf558606d86a1132a7dcca20403a SHA-256: e5a9ae1a330a3dd11360cf4eeef1c3bca58c13a863e096ca35e99a23b4d1fd4a
156 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing or trojan. It contains a link farm with numerous URLs pointing to other PDF files, many hosted on compromised WordPress sites or disposable domains. This suggests an attempt to lure users to malicious content or potentially for SEO poisoning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://medvor.ru/uplcv?utm_term=como+guardar+una+pagina+web+en+android PDF link annotation
    • https://sonerofset.com/userfiles/file/tigosas.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/gowovofimadetoj.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/bbbc156ff64a74514ee4cfb0655d23ed/47409619186.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/kukobifezel.pdfIn PDF document text
    • http://vaynhe.com/upload/files/rafemufikodiriwa.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/fsqarokl6b6ujlq20163gk2422/tefofojavuzapavuwese.pdfIn PDF document text
    • http://stepasidemedical.ie/images/uploads/file/dejuzajigirefisavirokaf.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613171da28f01---11210894720.pdfIn PDF document text
    • https://kawanmto.net/contents/files/28158907606.pdfIn PDF document text
    • http://lawfirm.vn/MINH/user_files/file/gudidinabebawifofoti.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/jusetibidukumebiliti.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/puxomilivuxujuzotunigik.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021090912342229.pdfIn PDF document text
    • http://aqua4you.hu/userfiles/file/92964681014.pdfIn PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/nezajijiwofu.pdfIn PDF document text
    • http://sprinter-lab.ru/content/File/lotonurar.pdfIn PDF document text
    • http://comitatoamiantovelodromo.org/userfiles/file/nimowetenon.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/file/fujopatijilujirofutepo.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/30490211565.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/93155704406.pdfIn PDF document text
    • http://krcatikyonetimi.com/userfiles/file/25390274471.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/vutowe.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_off0001019d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000119b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119B4 10780 bytes
SHA-256: 09327725deac1fba97f19bd544733fc94a53bf668fa759d8192f1e8d1d38120d
font_02_sfnt_off0001321d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321D 19280 bytes
SHA-256: bf1f0522fbd07ea74bc105c06cdb326c6771427673b19775fb3dea2b2e30ac7c