Malicious PDF — malware analysis report

Static analysis result for SHA-256 f166da9d6ecce496…

MALICIOUS

PDF

87.8 KB Created: 2021-09-04 14:17:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b18101b823aa8bd52c087a9ec60dac77 SHA-1: 2f1a0985ae1f0c1f502eb0a83c7c6edbbcf85f94 SHA-256: f166da9d6ecce49684bbbd130cb8dbd72d624a81da6ce12d8c68533084447a1a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, likely to distribute further malware or phishing content. The presence of multiple external URI heuristics and link farm indicators supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab80c844826---zomesugabaxifek.pdf In PDF document text
    • https://pezenasenchantee.fr/userfiles/file/51368448516.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160fbc1b37f0ce---28346922565.pdfIn PDF document text
    • https://people11people.gr/uploads/File/dolikobadatizojorufaboviw.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/sibujoni.pdfIn PDF document text
    • http://gniortho.com/files/Upload/file/kebomisanibon.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/mogerifevitesurerinidorar.pdfIn PDF document text
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/nijozizili.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/berewupeze.pdfIn PDF document text
    • http://badaranquehablar.com/userfiles/files/tukuzawivomulojazimer.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/595045a445fc4a530e6b9da157418967/zivipijekasop.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/1afb5e0829fb561f9f0d10aa18f7d0f4/xelopafomosujoz.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d455b085c---wokono.pdfIn PDF document text
    • http://synowka.pl/galeria/file/zumagelebopubaxafimufofu.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c74b3ae1a48---11022168777.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160856c01edab3---66021177997.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da77c70330---54682609370.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/4tpd557rnqm021lmjjc39jfo1b/zukabubuv.pdfIn PDF document text
    • https://thediamangroup.com/_images/files/51993339406.pdfIn PDF document text
    • http://camwater.org/media/files/23875431789.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2558509eae---50892962884.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ef7b2c7930---63680901779.pdfIn PDF document text
    • https://asiarsolutions.com/userfiles/file/2191746310.pdfIn PDF document text
    • http://slmj8.com/data/userfiles/files/tarowiwenonijekofuseva.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/zunemifemafitopev.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/xopewabivukudo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=improve+your+written+english+master+the+essentials+of+grammar+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_off0000f05a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF05A 17644 bytes
SHA-256: 9944529ef48d324916f2855741b22f9c75bb899444a2ec73ca07d0cca2ca7e1f
font_01_sfnt_off00011e3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E3F 11264 bytes
SHA-256: a08d7c6b0e246fd68b3b100eedf740eb8dac7e751e9644821893ac6b6b41f8f2
font_02_sfnt_off00013850.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13850 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1