Malicious PDF — malware analysis report

Static analysis result for SHA-256 b23571d47f08a33d…

MALICIOUS

PDF

75.6 KB Created: 2021-10-02 15:06:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: ea2c61ff3a3d21e12ac8e7b6e829725a SHA-1: 1cdfb4b88998819e515e92d1932860f940224bcf SHA-256: b23571d47f08a33daaa6f19a73903f6f4279495f668a9ad8dac0d662cc9cb281
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing trojan. It contains numerous embedded URLs that function as a link farm, directing users to download files, disguised as free movie content. The presence of external URIs and the link farm heuristic strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=spiderman+homecoming+free+movie PDF link annotation
    • http://iknow.pl/files/file/82257357115.pdfIn PDF document text
    • https://danfort.lv/userfiles/file/97141236572.pdfIn PDF document text
    • https://semut73.com/contents/files/45460504317.pdfIn PDF document text
    • http://zl369.net/userfiles/file/lixugozufuwili.pdfIn PDF document text
    • https://cfi-registration.amyhalter.com/buzzboxgift/img/userfiles/files/jezexunajafetetis.pdfIn PDF document text
    • https://afra24.com/basefile/afra24/files/welum.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/23338675344.pdfIn PDF document text
    • https://martabaktelor.com/contents/files/semigiloneniliwakodivud.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/zukix.pdfIn PDF document text
    • https://skl.deindrukdemo.nl/upload/files/rusawulixajidige.pdfIn PDF document text
    • http://pi-consulting.ch/download/73021011548.pdfIn PDF document text
    • http://ccshecea.org/upload/files/53209017767.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/17877051866.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/fimoboxiwavizozeken.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/29772602902.pdfIn PDF document text
    • http://kbo.pl/ckfinder/userfiles/files/lotorakojolepanedir.pdfIn PDF document text
    • http://paglialonga.it/userfiles/files/pomukapaj.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2d105e7ae---ginizegogikokuj.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a3e0db65d---wodirigopegab.pdfIn PDF document text
    • http://tianfonmm.com/d/files/52516457006.pdfIn PDF document text
    • http://hoadondientu-ptp.vn/images/ckeditor/files/palopemevomomudaxanapid.pdfIn PDF document text
    • https://euinsuti.uniluxgym.ro/app/webroot/files/userfiles/files/runadebibujatofikix.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/54633300211.pdfIn PDF document text
    • http://slovbau.sk/test/userfiles/file/61900019675.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/jugivudixerizavuxanifujob.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/fawipolunejumegepena.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/71440484629.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_off0000bc32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD449 10896 bytes
SHA-256: 42ad3ac66c22f61650d2e36ab608be5755fad93a68341d30d81419189c1c9d9a
font_02_sfnt_off0000ed0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0E 19816 bytes
SHA-256: 029f716c940888abb790cbe97b5177e508e2b8396e50a928c2797d3b796b7f7b