Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3b6a111e00e0029…

MALICIOUS

PDF

77.2 KB Created: 2021-09-04 12:18:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4ae422be3fb0a2ac4b99b1b33377c931 SHA-1: 41b2ac09c79bb5e81bce01e5303a6b31fa6d2703 SHA-256: e3b6a111e00e0029a6c6a1f77c182f56d8ac3bfe1c0b21fb80c6cea44d8772d8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to download further content from compromised CMS upload storage and disposable hosting. Although no scripts were directly extracted, the PDF structure and link farm behavior suggest an intent to facilitate the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • 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://aarhuskortet.dk/images/file/ponatep.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/ec698cc09532ef631ca08aad7e22aa18/bilamikuboxafar.pdf
    • https://psychologgia.pl/Upload/file/95988816662.pdf
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/951e526a3e0d3fe918ae0b44e194d02d/73525778426.pdf
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/ac7998cd3ec24dcbbc1a3adcace9630c/sizozunowisamixu.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160909b6920311---98723282079.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608927f371429---98377472802.pdf
    • http://nhactheducthammy.com/upload/files/lirotuzukajizusote.pdf
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/41a6ee2b4308b9430979102ab0250c26/79208062595.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d7e8b40c925---79495705298.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a659ee61d4c---30159652606.pdf
    • http://dawahcity.com/userfiles/file/tobawomino.pdf
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/79623027508.pdf
    • http://lamorenj.com/userfiles/files/fewuligivofarabenomomuxa.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160d2d7fe27266---26678440714.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/oacjfjk42lato622nhm5gjp91n/xeniripadigoneb.pdf
    • https://detskeihriska.eu/ckfinder/userfiles/files/didovolapesikivivikop.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/7d68d74abb0f57c472f1960c5207bf40/zenarosage.pdf
    • http://yas-center.ru/userfiles/file/fodolodujunekomafuwajef.pdf
    • https://grdr.org/paidel/ckfinder/userfiles/files/63471124554.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/e5a0e6cc330a6974e8f14c8dbdcf8a88/40500774727.pdf
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160babff2e6839---10539904778.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/9825eqt0s88tlet10r6cqnv584/nikidawenawifupidobewan.pdf
    • http://springbook.no/files/kojetowuv.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=concept+in+architecture+design+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_off0000c9f2.bin
97b5812ade831c9180210daf524fc6768a1ede89aba5dd06c8eefc949fed9860
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F2 16744 bytes
font_01_sfnt_off0000f543.bin
7dcffe18d5ac185271a89abacddba3baa74b247953ae13753dc5bd4726d23d4f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF543 10984 bytes
font_02_sfnt_off00010e84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E84 16792 bytes