Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c7fa689443b54f5…

MALICIOUS

PDF

84.2 KB Created: 2021-09-13 23:01:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b451b516aeed3f96bbb97466089f638b SHA-1: 5069fb0591b669b70d94e9dd68448ad9740e42b1 SHA-256: 8c7fa689443b54f59cf69cc7ad89d286844f408b5e3ba07fecd6c83387c57e3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The PDF structure and heuristic firings indicate it's likely an exploit delivery mechanism, potentially leading to further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://problemconsulting.com/img/download/files/tewelimovi.pdf In PDF document text
    • https://ehlibeytalimleri.com/resimler/files/90947724066.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16138d67bbf034---siluvetidujiz.pdfIn PDF document text
    • http://penzion-u-zamku.cz/files/file/54063102906.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/ja979jk1jj3uu4d4trtrf1pprl/13996727385.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/55957059537.pdfIn PDF document text
    • http://basse-normandie.annuaire-regional.com/ckfinder/userfiles/files/xerepapuxovapokuberibo.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/75627634251.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/buxepelubekeg.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/watanobo.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/sepezukuzipimeka.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/35266795501.pdfIn PDF document text
    • http://fzcce.com/aimgs/uload/files/tapolopewufowuvakexume.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/pisamewun.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/79189903933.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/volakewagujiwo.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210911_43A674488C4747B8.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/93255376327.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/jazexerufaza.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/43i972282ikukfgulgmku0iss2/19453415684.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/b0l074pfr4q2go7pvp973ooue1/weditolipoba.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/fosituzunalazurizujega.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/2fr137hepks19ljoplgtk111vi/89967362973.pdfIn PDF document text
    • http://canoto.us/Images_upload/files/60430092652.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=the+art+of+stress+free+productivity+pdfPDF link annotation
    • 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_off0000e40c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC23 10812 bytes
SHA-256: 4c7cc8719fda043ed99a589d566285cd10de0422231583b4ecb36ea79a2e7d48
font_02_sfnt_off00011548.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11548 17736 bytes
SHA-256: e640641571634cb781986bae5399b7d9c1119c5c0fbbb971f32a6c07cd86cffc