Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea0837375a19c451…

MALICIOUS

PDF

79.2 KB Created: 2021-09-20 07:10:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8f04888d516d552baa0b5c7c45932570 SHA-1: 74efd11acf4bff47088b1c6968bc46e89f8a033d SHA-256: ea0837375a19c45180c9eb3a6888f52bea1871a3ebb341a8544fdaf95d53c0f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The heuristics indicate the document functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests an intent to distribute malicious content or phish credentials through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ecohort.info/userfiles/files/43545276034.pdf In PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/bd72d54080b70d7446c69bbf303104ef/fivitiku.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16135f133b6ee3---zegizirixaboguti.pdfIn PDF document text
    • http://z-sinpro.com/upload/files/zikunonexib.pdfIn PDF document text
    • http://salamino.pl/userfiles/file/fetel.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1613be77e12488---65188734100.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/sunofukesufupigasab.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/73996391201.pdfIn PDF document text
    • https://wrd13.com/force/file/xikibulizakuzatujebovomup.pdfIn PDF document text
    • https://biocoils.com/img/file/79309170277.pdfIn PDF document text
    • http://ji-tien.com/userfiles/file/lowofijenere.pdfIn PDF document text
    • http://lovesenergy.com/file/23456175610.pdfIn PDF document text
    • https://morethancars.eu/uploads/edytor/file/37699311380.pdfIn PDF document text
    • https://www.aaptuk.org/ckfinder/userfiles/files/gabapopekavilowawopikowe.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/7730076461.pdfIn PDF document text
    • https://client-sms.com/ckfinder/userfiles/files/gukajaso.pdfIn PDF document text
    • http://doggystylzgrooming.com/admin/photos/file/poruvew.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/zijuw.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210919_062342.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/putuvefanozafas.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/91925022949.pdfIn PDF document text
    • http://mprime.net/ckfinder/userfiles/files/58982962694.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/sobimakefolibenap.pdfIn PDF document text
    • http://fruitsad.pl/images/file/45021451616.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=facebook+auto+liker+2021+apkPDF 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_off0000d28a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD28A 10700 bytes
SHA-256: 2ff85c1168d4a2eca8286a3808bdb1461872d0bc149013f8873f1cbd9d2dcb61
font_01_sfnt_off0000eb12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB12 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010324.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10324 17164 bytes
SHA-256: b6d3081e688f7f97723fdbb1e0a7e5c20259b01e8612a329cc94d1d6a5187d50