Malicious PDF — malware analysis report

Static analysis result for SHA-256 acd835c85086752a…

MALICIOUS

PDF

89.5 KB Created: 2021-06-23 08:51:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e28269e230b87a6053bfb862f8951096 SHA-1: cf3f5ce5a5ca505bd5b56893ed7f8219fca80770 SHA-256: acd835c85086752a2e005417ab020a05bafc2630863526888158514a99f89a18
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript T1553.005 Security Software Curtailment

This PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The document body and heuristics suggest a social engineering lure related to 'blocking adobe activation', likely a pretext to convince the user to disable security software. The presence of numerous links to compromised WordPress sites hosting PDF files further supports a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • 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://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160739f88b5cdd---mutozaxatafusikomome.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/88a6ad0b259d4c1cd41aec1231006ae0/pitusivuwerakogotugipi.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/f794f16a6b3286212bf85fb085d48888/47553962815.pdf
    • http://abwingsbuffalo.com/uploads/files/95295023761.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/a953676b0ebea8e5fc2850b895f9ce53/90625501874.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa382cf30c8---ramujipesaxovat.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/gfc47hlj56c5irvmp9oeu7ogh0/46819193113.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4a4867ca70---89855094811.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/fmhhomsv0arbj4ena26vce49m5/baxewidetajesuzavumogib.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608d549063d62---51199477769.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093b9e890046---dajadujunazagadowale.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce0c7e6490b---975691093.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b31f759d75a---vupolipiledodon.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/3d83ee6070530a23ed970cb87395b687/wunopenawix.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb25b0805e---80131821275.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=blocking+adobe+activation
    • 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://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e89b.bin
fc2ec622ec6405c775d3cc7e510d0f80b927ed2bc87ffca32f2265ea725e1b73
pdf-font-stream PDF embedded font (sfnt) at offset 0xE89B 17412 bytes
font_01_sfnt_off00011f2c.bin
fe90a871b98cf639afc362e3a10f3d8d77a9db6d131f3f3c3ee6913eb385428f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F2C 5148 bytes
font_02_sfnt_off000130cb.bin
29facf311a432f4c7181d4630be9943d855386bfda01926126587d23dc879d36
pdf-font-stream PDF embedded font (sfnt) at offset 0x130CB 11272 bytes