Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b7a668cee1e2bef…

MALICIOUS

PDF

79.6 KB Created: 2021-09-02 07:26:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6cb17a6da54274e5dbd67ed4b5464cd6 SHA-1: 052f9260d29c0b2b4ee8f671e637de4e0e3b0954 SHA-256: 4b7a668cee1e2bef15e22fd3c97f16534f28d72737cb5447daccc780fc5b76a5
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites and other disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the structure and URL patterns are consistent with exploitation and redirection to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://enslev-anlaegsservice.dk/userfiles/file/nubud.pdf In PDF document text
    • https://digireg.ch/upload/40349313667.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/9936886dd06b07a620714cf41269ed3b/fufarulukosepasom.pdfIn PDF document text
    • http://pyramidplaster.com/file_media/file_image/file/8546955670.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/54668275277.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac92f43708d---65672848072.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e45b6beb5---mowekolofomamisole.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/0db2c89f0ba3a51bfcba55c2cc2c2865/xitufodovoz.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/0c61321d318e8f2b5d8cd372592d59c1/3934411387.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/b104f78450bec96d986f85ae5721815f/suvopezetixep.pdfIn PDF document text
    • http://jainfarms.com/uploads/kalawipemotonubozox.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021050405484773499.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e5f0346e3---jumevikunegazupitedamera.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9bd28116e---livoworef.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/f4df969788a3a31a2e0aad9a4cdba906/ninelamotatewujusuti.pdfIn PDF document text
    • http://tmacfashion.com/ckfinder/userfiles/files/polavunozumamadetoziti.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160c97599e16cd---2441015287.pdfIn PDF document text
    • http://uchid.com/uploads/file/77414034766.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/vanofidevavowexe.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/84028135388.pdfIn PDF document text
    • https://fizjolech.pl/userfiles/file/milileworijurozepurif.pdfIn PDF document text
    • https://lee-trading.tw/archive/upload/files/kinigojepatenemu.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/25247705103.pdfIn PDF document text
    • http://www.fotolia.com'&gtIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+change+the+font+of+all+slides+in+powerpointPDF link annotation
    • http://www.fotolia.comIn 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_off0000d0e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0E4 10976 bytes
SHA-256: 8b46c413dfecc4fd920b039ef55fd77e831bf1b403e758a138f0712b3f7e6c1f
font_01_sfnt_off0000ea20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA20 17480 bytes
SHA-256: 7937f0a3694f01f4f8856ceb88191f9c3d680106f6348ca56767c473466d906d
font_02_sfnt_off000116ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1