Malicious PDF — malware analysis report

Static analysis result for SHA-256 a55eaf65d6e9065d…

MALICIOUS

PDF

67.9 KB Created: 2021-09-27 03:09:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 569b5246af6ed92bacbdc393473c9ec7 SHA-1: 35c849ffd0fb6f45a40680b094bfe545601a23ee SHA-256: a55eaf65d6e9065d83254a9f976e80f28deada66532d7ee38be1f9c8906c6021
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external links, many of which are hosted on compromised websites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classifier flagging further supports its malicious nature. The document body, though heavily obfuscated, indicates it was generated by wkhtmltopdf, a tool often used to create PDF documents from web content, aligning with the phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://synerhu.ru/uplcv?utm_term=download+google+play+store+app+white+shopping+bag PDF link annotation
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/hd68ajg7gqd3ffurfntp8v93i3/gikapopavevizewubevimuguv.pdfIn PDF document text
    • https://alansglobalservices.com/ckfinder/userfiles/files/xojotojufubo.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/77982960878.pdfIn PDF document text
    • http://transgusto.ch/userfiles/file/zuluvafafajuxipavimiwu.pdfIn PDF document text
    • https://www.ijestr.com/ckfinder/userfiles/files/4628279323.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/85107179373.pdfIn PDF document text
    • https://kipass.fr/userfiles/file/79132977819.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/86828130475.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16150f408a42a1---gujofivu.pdfIn PDF document text
    • http://liderzy.natura2000.pl/imgturysta/files/74700370195.pdfIn PDF document text
    • http://www.omt.ntou.edu.tw/ckfinder/userfiles/files/17481375342.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/76445826853.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130174bdbf86---38616845369.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/5792429558.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/47928724140.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/penabug.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/7v5qerthrrbc64q1ou92jju3vd/35819601519.pdfIn PDF document text
    • http://cornaredo.gattinonimondodivacanze.it/themes/userfiles/files/wemas.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1ac94686068aae1c134befb1a48ce027/kezawukowawizokasuzugiru.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/japofawumoduxisesiviraj.pdfIn PDF document text
    • http://asid.rw/userfiles/file/girisawiliwaroma.pdfIn PDF document text
    • 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_off0000ab25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAB25 11012 bytes
SHA-256: 8136d99b089f2d7f8396b9efd1dad00656dee819a95f616eca467f0b819fcad3
font_01_sfnt_off0000c44e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC44E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dc60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC60 14512 bytes
SHA-256: 5dec6957306011bade263dc2b1ac0950a28ec9ce31e689523be544eee821fcd9