Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb3b54566845f90d…

MALICIOUS

PDF

79.7 KB Created: 2021-07-14 02:35:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a4569c4ab550a62fb184e20e8dc52d3d SHA-1: 820c82ab030b86c11f5d6dd9655007bd72b64d25 SHA-256: fb3b54566845f90d14bedc36eccc3015b0983f6663e7f593d91d468a0e35936a
184 Risk Score

Malware Insights

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

The PDF contains numerous links to external sites, many of which are hosted on compromised WordPress uploads or disposable domains, suggesting a link farm designed to distribute malware. Heuristics indicate a malicious ML classification, a callback lure, and a visual download button, all pointing towards a phishing or scam attempt. ClamAV also detected this file as Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 8

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://pistant.ru/uplcv?utm_term=change+of+address+michigan+enhanced+driver%27s+license
    • http://s-privod.ru/userfiles/file/tejufisezifaxa.pdf
    • http://ghalemdi.com/userfiles/file/zuxedal.pdf
    • https://aawyx.com/sites/default/imageuser/file/noxawunud.pdf
    • http://www.nomorcantikjoss.com/file/17849090296.pdf
    • http://ksnjl.com/userfiles/files/96915736753.pdf
    • http://okulsanmalatya.com/imgup/file/3122635191.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072bed565e7a---xobunub.pdf
    • https://paklya.su/design/img/upload/file/mugutigoxanotajekinux.pdf
    • http://shreejians.com/userfiles/file/bugunomex.pdf
    • http://mulroyenvironmental.ie/userfiles/file/niziwozabup.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160744c3440145---80469515537.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/a10da5bb7f142e84a346f2691f33bfe5/pinotivivigobaseku.pdf
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/iu1c0as6bra72mfirq3b29al14/66433896505.pdf
    • https://ratco-hardware.com/Ups/files/luwedosijalorarazejojik.pdf
    • https://chupwo.com/editor_upload/file/12831053664.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/16088be79d38d8---kekabiger.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c73f3bdbeea---penanamaduzoba.pdf
    • https://mavibusiness.it/file/21347942228.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075cb471a329---96987627047.pdf
    • http://allgeology.ru/ckfinder/userfiles/files/dalix.pdf
    • https://aterhesseg.com/up_image/file/3806895347.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/m55keiufuil4k1enj0td5cq9ka/muruke.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088b7256f975---68583743419.pdf
    • https://transpack-krumbach.de/_upload_bilder/_filemanager/file/napivonalatakofokog.pdf
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/ipc2is9iqdi3r8qiojvfe4hfgn/luturezak.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160789784eda77---81590584527.pdf
    • 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_off0000d528.bin
232410822fd0a62ca6a65829aadd9d2aa318fac1eec33f49ecf56e0bf8c547d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD528 16276 bytes
font_01_sfnt_off0000ff77.bin
6dcf03ca61861316a3e1c30253928c084e0e0b76256c7a5297cf5f7adb5a1349
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF77 10956 bytes
font_02_sfnt_off00011892.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11892 16792 bytes