Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b3c8e150f087179…

MALICIOUS

PDF

68.8 KB Created: 2021-10-04 10:06:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 99df083691534a9899d547de4bd6b639 SHA-1: a74f8fd4823a788067ebe6da10eec4118ced2770 SHA-256: 4b3c8e150f087179db163378983cd6b729fcf3cb94468ca7cfe377721da6b47c
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution scheme. The presence of PDF link farm heuristics further supports this, indicating the document's primary purpose is to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://oniceh.ru/uplcv?utm_term=greed+in+mexican+spanish PDF link annotation
    • http://cppzone.ru/users/blogs/file/82976210398.pdfIn PDF document text
    • https://aokman-drive.com/d/files/gizutifuxefifasotuta.pdfIn PDF document text
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/In PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/fumokikelofepexa.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/vuzunuzemobuvolaremodad.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/fekulexidoz.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/86752623240.pdfIn PDF document text
    • http://aasghsflqsae.handylover.com/upload/files/feguzuximor.pdfIn PDF document text
    • http://sozopolihills.com/userfiles/file/romevolajugopunefikezuza.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/87794667514.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615808a63c650---pufusunibibemo.pdfIn PDF document text
    • https://vietcuongcorp.com/uploads/news/files/nusedajoba.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/paburaruviw.pdfIn PDF document text
    • https://samngaimarble.com/html_upload/file/63514407588.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/file/60326661062.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/pawigu.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9073edefe75e1cfb5d055891e52fbd3c/totopa.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/files/95973074773.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/4rjtgl1n2ud3cl9nvu29b2veft/73032608972.pdfIn PDF document text
    • http://wmasgroup.com/userfiles/file/14844989308.pdfIn PDF document text
    • https://thehideawayresortpattaya.com/userfiles/files/newerudafutowunope.pdfIn PDF document text
    • https://andreivieru.com/ckfinder/userfiles/files/gakub.pdfIn PDF document text
    • 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_off0000afb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB0 10656 bytes
SHA-256: 5716d1daa65d54cd9eb1951a385f6b1691cb58f7bd3857660c808f4e2cf79e4f
font_01_sfnt_off0000c7d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dfe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE9 15112 bytes
SHA-256: e349c69a0fd8e417ecf3bc4ccd25ace0c2a959aec720d2ab4ea62b9fc1472f5f