Malicious PDF — malware analysis report

Static analysis result for SHA-256 643cea87405bdbad…

MALICIOUS

PDF

74.3 KB Created: 2021-09-17 14:36:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f47342494ffd4207a127a33c19eea64c SHA-1: 02c72fed95c6413af1d5502b2f982efd1c484e2e SHA-256: 643cea87405bdbadfc3f2ec14b58a93a8103939f2ade42a55f1714b9a010bc35
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the collection of malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://ukkies.be/userfiles/file/soxofaxim.pdf In PDF document text
    • http://lideparts.com/userfiles/file/1630559244.pdfIn PDF document text
    • http://baracenter.be/userfiles/file/fanewagebobebaf.pdfIn PDF document text
    • http://ingpoggi.eu/userfiles/files/matonimudibepanixubo.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/26309697731.pdfIn PDF document text
    • https://malayalamfoundation.org/admin/my_files/file/bemofu.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210905085301.pdfIn PDF document text
    • http://xn--aknmedcal-wpbe.com/uploads/file/zegefibevijatevuloj.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161431e795ce89---9739994617.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/25b44d6c951c449c2e2b44a1ceb97ed4/62243065085.pdfIn PDF document text
    • http://reopen911.info/media/file/kagerafa.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/82795735853.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/lewepozitanusizadir.pdfIn PDF document text
    • http://studiolauramoschini.it/userfiles/files/gavejafixewiduwomanerif.pdfIn PDF document text
    • http://showdoimovel.com/files/files/kuxojupen.pdfIn PDF document text
    • http://unionnutritech.com/upload/files/zosevi.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/xekojejiluxufanuxunowo.pdfIn PDF document text
    • https://franchisebusinessadvisors.franchisebrokerwebsites.com/broker-site/files/files/tojilivelu.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/63qfm74dfmhgl6kvt44mtavrn8/babosapemunaxi.pdfIn PDF document text
    • https://akilanews.com/ckfinder/userfiles/files/69590938307.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/vopizonalejetale.pdfIn PDF document text
    • http://metrominicabs.com/survey/userfiles/files/liguvumezavojiro.pdfIn PDF document text
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/28519159314.pdfIn PDF document text
    • https://valkexclusief.reviewz.eu/app/webroot/files/userfiles/files/turedejapufimabifaja.pdfIn PDF document text
    • http://ji-tien.com/userfiles/file/zukuladupupimewobave.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=multivariable+calculus+with+applications+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_off0000badb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBADB 11100 bytes
SHA-256: 1a227eb3eb0460afc8e55eafd3198f3e6f99950a6f6f33978465981ab13f0779
font_01_sfnt_off0000d48a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD48A 18704 bytes
SHA-256: 6f71ae09a63be6484271687a79020074f00fa0ff33961178ff7c45125d2afc67
font_02_sfnt_off00010306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10306 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1