Malicious PDF — malware analysis report

Static analysis result for SHA-256 91df17d8ee20e8ad…

MALICIOUS

PDF

71.5 KB Created: 2021-09-03 19:10:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c8c3ea24562e12b8fdb3f2c00000fafd SHA-1: 3f18e3992699ac834ed6d26d2bf8ddce60a0578c SHA-256: 91df17d8ee20e8adac58f7635422e2ef5987f51c113dc91c4c7b3b0dead72b41
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://careersourceokaloosawalton.com/files/public/9299046036.pdf In PDF document text
    • http://stavclearing.ru/upload/files/vusog.pdfIn PDF document text
    • https://escaletravel.com/userfiles/files/26748205677.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/juvek.pdfIn PDF document text
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/65551442393.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae6e22da529---73955337262.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/53744351149.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/18825235981.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/34059234281.pdfIn PDF document text
    • http://mamnonlittlesun.com/upload/files/5461613808.pdfIn PDF document text
    • http://www.climatisur.com/ckfinder/userfiles/files/54562329807.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe63dc06b0---34647341753.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/58409924317.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612c195015b5f---vuvanowoxetagizurojareku.pdfIn PDF document text
    • http://studio-orlandini.com/userfiles/files/8460172779.pdfIn PDF document text
    • http://ch-bovi.com/upload/files/8853690521.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/3553309162.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/nekowesefatavuxidik.pdfIn PDF document text
    • http://yanarfabrics.com/firma/files/nukupizisepuzejipo.pdfIn PDF document text
    • http://cambridgekapurthala.com/damana/userfiles/file/jumabapinifodovetav.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/mujonemelojuw.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///51015348990.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///76315659836.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e868419626---4699393469.pdfIn PDF document text
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160700bdd35f57---kigakidojejilidafigas.pdfIn PDF document text
    • https://italvaping.com/file/bevokivivoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=core+clinical+cases+self+assessment+for+medical+students+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_off0000b821.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB821 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d033.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD033 14920 bytes
SHA-256: 616f672f6abe8db79d6a374b7797e18380cfb30191c5f981c9a898d6775d43d3
font_02_sfnt_off0000f622.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF622 10912 bytes
SHA-256: f54fc1c0327aad1249a0822b9decfc1a1e36c18669f9b8330e73d6f5e1b2df12