Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fc23aced383caf5…

MALICIOUS

PDF

91.5 KB Created: 2021-08-06 20:46:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3dc6549fc3fc64976338df458a207650 SHA-1: 7b8ea019cb58da3c377f5e095fa8236dde497da8 SHA-256: 3fc23aced383caf5780dc25d251900db76e5303e1b6fad8b1380fdbbd871b231
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/kro641vrc6sumcavm1af8sgiba/39540976107.pdf In PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/87250834688.pdfIn PDF document text
    • http://gumberryoleschool.com/clients/33891/File/kodasekinus.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/88237021016.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/08/05/file/fevotobizumeba.pdfIn PDF document text
    • https://mindspacepsytherapy.com/upload/ckfinder_temp/files/20210614025122.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16080e6faa953d---metijupoxepanakivigodexa.pdfIn PDF document text
    • https://ratco-hardware.com/Ups/files/dimanejebebemafuvu.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/18216415831.pdfIn PDF document text
    • http://gemaeldeundobjekte.de/uploads/files/jevatenosiwotujijesa.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/kinizenalogeremamesaputum.pdfIn PDF document text
    • http://xsteelstock.com/d/files/birojo.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/govevuberaxaduto.pdfIn PDF document text
    • https://dichocungtoi.com/userfiles/file/90611755953.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609633e7f2b81---mawojijam.pdfIn PDF document text
    • https://paperland.bg/uploads/file/lirefivalox.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b684cb13d9---18389331180.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/92328534102.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6b321965ae---29700331815.pdfIn PDF document text
    • http://csc0512.com/userfiles/file/20210804084234_3e0ne0.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/e84f4eb8906724b58b50f68db9957b19/pajuduwabonovipuwufuw.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ea455f634---43640224732.pdfIn PDF document text
    • https://unosms.us/userfiles/file/55089928795.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=libros+para+aprender+ingl%C3%A9s+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_off0000ffad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000117bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117BF 18168 bytes
SHA-256: eaafe63a7432e09132141e42f4cfce49ef31fe173ae4fca017ea3afd2c949ed5
font_02_sfnt_off00014566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14566 10824 bytes
SHA-256: 0a3f57b6fedb7bdc08bc0939706dcfe92a6240aa471c38fdeb269326c1c03cc8