Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1674e6d8b3e5143…

MALICIOUS

PDF

82.1 KB Created: 2021-09-07 11:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d535489c32795da2ece27882248549c SHA-1: 6c10c5c3d446e9bce5fd58a97a0231e4244737bd SHA-256: c1674e6d8b3e51434f1691fbbb4f156b92121924370b63cd37653d81d23e5277
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The file contains numerous embedded URLs, many pointing to compromised websites or link farms, suggesting an attempt to redirect users to malicious content. The authoring application 'wkhtmltopdf' is unusual for a typical document and may be used to obfuscate the malicious nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pixomot.ru/uplcv?utm_term=lista+verbos+irregulares+y+regulares+pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/08017bfb8d3dfa12a297b8cd6462dc23/degim.pdf
    • http://pechati-piter.ru/userfiles/file/vesaxesaviliter.pdf
    • https://mygenius.ru/admin/ckfinder/userfiles/files/vomifuki.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/rovifunovi.pdf
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/ef6e24ac3e003cd41676483e393d714b/dunefixinizarovofo.pdf
    • https://hansenlight.com/UploadFile/files/25778844555.pdf
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/f7e4846df43ece9b894bde5ae14545d3/82766105874.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16088f36359e1d---wadurejegan.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7a8ba28fd---50326987127.pdf
    • http://bulongvungtau.com/media/ftp/file/bewuk.pdf
    • https://kede.org/userfiles/file/30990459763.pdf
    • https://jechrina.gr/FCKeditor/userimages/file/sewozuwoboju.pdf
    • https://ncsccalgary.com/userfiles/files/47150192971.pdf
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/a702328bb7196e5eb3bffe473be712be/46447076953.pdf
    • http://asfalon.com/__files/file/56832719744.pdf
    • http://wojno-stal.pl/pliki/file/kulivuviroresozafozujikif.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/r6me2mertj2v56pq91fe6sknq1/94712890621.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/crf3d1td9r77mabet2bldeo800/dedimesatilexa.pdf
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/4535affaa45bf3b3cff723ac10a73d2e/99465963481.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/45834488295.pdf
    • http://adveotec.com/img/file/zotisaso.pdf
    • http://www.facyt.com.ar/ckfinder/userfiles/files/lijotejofirit.pdf
    • https://tckontrola.hr/files/33697364104.pdf
    • https://atasuorganiktarim.com/upload/ckfinder/files/98973489876.pdf
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/lejukunikipufufebenag.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_off0000d5dd.bin
85d40c61e5b3877fb66c84ada6bf0d12e5080b7c52fc8569daa33a09ebff2c94
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5DD 10944 bytes
font_01_sfnt_off0000eefc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFC 16792 bytes
font_02_sfnt_off0001070e.bin
b953bda1c77d0a78d999781ffd66aa29aed85a63b45cf6b3eb951cc972ff182c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1070E 20220 bytes