Malicious PDF — malware analysis report

Static analysis result for SHA-256 03959c812f6b1b66…

MALICIOUS

PDF

74.1 KB Created: 2021-09-13 17:38:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2b7395a56d79f1aceddf53cf5ebad8e0 SHA-1: a2e1c2e141508a86dce92bfa65a36ad84d00c449 SHA-256: 03959c812f6b1b6621b169292b5eceeba3a734ae7ef4fba87a6fcee77e4698fb
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads and disposable hosting. The embedded URLs suggest an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 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://p-jtech.com/userData/board/file/73094497378.pdf
    • http://www.naraihillgolf.com/admin/userfiles/file/vewolirabonar.pdf
    • https://toocapen.com/files/89544227057.pdf
    • http://www.ez4parcel.net/upfile/files/2021/09/12/33900559061.pdf
    • http://jrmhandling.nl/upload/file/bukiruli.pdf
    • http://ctm.it/userfiles/file/kirixodagiropudibura.pdf
    • https://martan.es/cenavarra_userfiles/files/17094001202.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132beb73fe4a---jagudalexutidusabibov.pdf
    • http://novelinternationalschool.com/ckfinder/userfiles/files/jowemivusewunuvev.pdf
    • http://022-web.cn/uploadfile/file/20210906170259388.pdf
    • http://gaushalango.com/uploaded_files/userfiles/files/6742306773.pdf
    • https://ip-kamera-rendszer.nuttydog.hu/ckfinder/userfiles/files/tonukidisorigexid.pdf
    • http://caogenzhiben.com/filespath/files/20210907092935.pdf
    • http://massiimo.com/piceditor/file/44923220434.pdf
    • http://hardiebase.com/uploads/assets/filefile/26750400841.pdf
    • https://impulsa.mantareys.net/uploads/plantillas/files/kejununufebejebitu.pdf
    • http://nomayaku.com/userfiles/file/35407612019.pdf
    • http://businessvaluationapp.com/fck_files/file/95522083153.pdf
    • http://caogenzhiben.com/filespath/files/20210904075153.pdf
    • http://warehousetraining.ie/images/gutoposadipefapef.pdf
    • https://jmtours.co/aym_image/files/womaravudadewatogemi.pdf
    • http://na-bytecek.cz/UserFiles/File/judonewe.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/5df943cba5804272a90411dd0ad4569c/gonub.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161302d5e188f7---13377495154.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=best+of+five+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bd23.bin
d33aa20880f85d9cac0f48124bbcf80969e8dca148240ece5740cac84a736105
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD23 18068 bytes
font_01_sfnt_off0000eb88.bin
22da2c53f321a87d1ba40206d5c17c9965b90e94729354eaf16070fe5a4a75d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB88 10312 bytes
font_02_sfnt_off00010310.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10310 16792 bytes