Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4e4cfec372161be…

MALICIOUS

PDF

88.3 KB Created: 2021-09-06 12:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ca8809046420d5b98b56e3c5e08d20d2 SHA-1: 707eccad37e9968e5674e56400509dd9068dbef4 SHA-256: c4e4cfec372161bef149dd13eccd62100513160554a42cc149cb1e1dd8702eb3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to lure users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

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 https://duel.pl/userfiles/file/tetugerakozuxunepapuwikek.pdf In PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/a927d1774fdae627a24ab3c0f8eb4581/sowapi.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/wobanosirimofejinaxenike.pdfIn PDF document text
    • http://samtle.net/ckupload/files/58297334551.pdfIn PDF document text
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8611a58eb---29582504303.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210715_030104.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609d686dcdf99---5162131652.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/supavugurekepi.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/8bea1cb420db6586bf981dca25f9ecd6/nukisoxubefasetub.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb1050676b---rizepafugedito.pdfIn PDF document text
    • http://burnettefamilyreunion2021.com/clients/867108/File/91753191330.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/58048382503.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/bb1972fb767ddf1121937cdcba4f326d/79052138577.pdfIn PDF document text
    • http://armanetti.com/images/42635982340.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610f0b5d8a1d4---32839998565.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/a60ad3f57927ae408f5d256a89a9eee1/raxemuladajosofugavo.pdfIn PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/74984d2c98fce114f46c827b56c54c5a/sufepakuludokeluwil.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/berigikakiromufonib.pdfIn PDF document text
    • http://biotledlight.com/userfiles/file///solejubolaxilajaxilif.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1608401ad21527---mulikulufilij.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/63396489017.pdfIn PDF document text
    • http://wasserburg.pl/userfiles/file/12760214903.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/garijiworedapujitumakup.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/koboxagoduna.pdfIn PDF document text
    • https://comptables-publics.fr/userfiles/file/34351675362.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1622ac595---25489785695.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=l%27oiseau+bleu+pdf+libre+de+droitPDF 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_off0000ed38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED38 10616 bytes
SHA-256: f9ede5d9d1a0d432aebb51bc40d10eb6ab4a651a50da2b538973e258a4a9d152
font_01_sfnt_off00010574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10574 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D86 20588 bytes
SHA-256: 680146bb772786df2dcea51a18fd12c77b47a5814af70b8383aeec06385691c6