Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8594d8c578b2a26…

MALICIOUS

PDF

74.2 KB Created: 2021-09-05 16:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0e69d802dcd0dedac524a862dd3289bd SHA-1: 0b900f945a20ec535e73faad4c46b9a605cd986c SHA-256: f8594d8c578b2a26babe13e8815a8ec447680a035492e547a1f99e03cd646b98
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is a tactic for distributing malicious content or phishing. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://xn--aknmedical-yub.com/uploads/file/24989003521.pdf In PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/lunotopaw.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b9649d4b2cc---rapotudasavewodidomozuma.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/56591130579.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/9689164339.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/vuzuvakuzi.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/44035133585.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/65822379241.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb587538f0---41917518548.pdfIn PDF document text
    • http://playonathletics.com/userfiles/file/gizunigukapawavoji.pdfIn PDF document text
    • http://billsky.ee/files/file/jedenekowekozudemukal.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/b3ba71490665226ab6e063927979c3bd/4298419309.pdfIn PDF document text
    • https://thuaphatlaihoanghuy.com/uploads/files/sowujubamejive.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/nipibuxumirisunij.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16085c3a75c659---95520588496.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/jatedokosirafesepi.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/xagusonizuworavebogob.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/gokejibotovareladoruj.pdfIn PDF document text
    • http://telekommarketing.com/firme_data/files/35273228654.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/55487171456.pdfIn PDF document text
    • http://maxbrio.kr/files/files/jaluxerejomu.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/87657481471.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/wajufala.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16126e9b7f1474---42342867578.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/90848570691.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=citizen+eco+drive+skyhawk+titanium+manualPDF 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_off0000b7dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF3 11184 bytes
SHA-256: a85c6068422068799e769ace9cdf9b8cc1a3690060c8a8bee72d592bb3d43bc1
font_02_sfnt_off0000ea14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA14 18868 bytes
SHA-256: 5371d2d00ab4858277503c482e2270f9602c240d48790c1cbd3ab28bcd180665