Malicious PDF — malware analysis report

Static analysis result for SHA-256 c571ee3c800837f1…

MALICIOUS

PDF

83.7 KB Created: 2021-09-07 04:03:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ac6da4ef5b07c8ad379faf0df2cfc616 SHA-1: be636b622ff29eaa832eccd277a9c71f37afe433 SHA-256: c571ee3c800837f117b442148c067120ccd1cd12565915b486c651bbda09033d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also functions as a link farm, pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites hosting PDF files, suggesting a distribution mechanism for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f521674588---92802041036.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/38d717e5edac1e87f2f707d01081617d/gegafitumoruxevebewabufal.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160fe45a81071a---15338253024.pdf
    • http://atut-biuro.com/uploaded/file/84745327075.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/8f2ea901afcaaec8b3b7b8e827debcb6/52538375829.pdf
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/zimifedusave.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc25314dd0---dezasi.pdf
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/678a9f284425ab9d127614f336d27220/titubesurofujijexi.pdf
    • https://femagnet.com/upload/edu/article/file/18875288714.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/podapoguremebidakot.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbde8dcc15---91582397816.pdf
    • http://metallpress.info/files/gutunamune.pdf
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/3492037bd3b5cf89451196df031c3b3d/95539158187.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/ca810232a1f1dc4427db4c90e8443062/64219394076.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ecb84b144---9986753951.pdf
    • https://eventaipei.com/upload/files/51305746367.pdf
    • http://aitrans.cn/UploadFile/file/F1202106200417503390.pdf
    • http://dzbnf.com/upload/file///patosafitesewi.pdf
    • http://prplus4u.com/ckupload/files/voxodogotuzomamo.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a921691ae81---71240486126.pdf
    • http://lisaarkinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61162446242.pdf
    • http://chinhsuasolieu.com/media/files/kapikovogaf.pdf
    • http://caminodesantiagoenmoto.com/assets/ckfinder/core/connector/php/uploads/files/belupowasezeke.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=flyers+reading+and+writing+test+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_off0000e07e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE07E 16792 bytes
font_01_sfnt_off0000f890.bin
c8372c58717d67fd1566344df2d4ba704ea1e371bce618ddbb65acf65afb032c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF890 18292 bytes
font_02_sfnt_off00012836.bin
1a2bacaca9e319d004b8383c7dffe5bdafef412615c7520e59c70854ccaa45b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12836 10728 bytes