Malicious PDF — malware analysis report

Static analysis result for SHA-256 d28af8d532b38d0d…

MALICIOUS

PDF

70.4 KB Created: 2021-10-04 01:58:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9d23005ae8dd274c70a8bd8eb0a890bb SHA-1: 96483049d0c6ec481c1d39d772cc2fa67d914a55 SHA-256: d28af8d532b38d0d480b99a7fc05552e2f9e3221b517c1a0f032275423cf30de
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination. Although no scripts were explicitly extracted, the nature of the embedded URLs and the overall structure point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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 http://tramtronbetong.com/uploads/userfiles/file/lazugamenemewakuxarow.pdf In PDF document text
    • http://mayjack.com/upload/files/lodibobexufapekubo.pdfIn PDF document text
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/patogunisanugutita.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210927075708.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/87391216066.pdfIn PDF document text
    • https://fotografski-studio.kost.si/userfiles/file/melodajot.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/62804301823.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/41731675545.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/47354204517.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/7017868706.pdfIn PDF document text
    • http://www.biharikft.hu/bihari-admin/ckfinder/userfiles/files/19524633866.pdfIn PDF document text
    • http://portalinmobiliario24.com/uploades/fckeditorfile/vatelefezanaxadazisibot.pdfIn PDF document text
    • http://newabel.com/ckfinder/userfiles/files/tipibive.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/karigulogidakitemuti.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/jijezofazitasoxijimigib.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/tugafafisinebisupube.pdfIn PDF document text
    • http://kids-ex.com/images/blog/file/mowepelosalekusalovop.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/39963349867.pdfIn PDF document text
    • http://lnv-cnc.gr/userfiles/file/230759770.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/rutuduw.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/d3056b0a359bfb961cdb94d2ff3af5c1/37975539469.pdfIn PDF document text
    • http://vilniausgreziniai.lt/userfiles/file/72060993208.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/75729861755.pdfIn PDF document text
    • http://emblem4home.com/UserFiles/Member/File/70877650146.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/10bd5bfa2c3ce3e2d06bb924165ec27b/vizuwekezomuvetadutigewo.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/2021913648106308.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+many+ml+is+one+bottle+of+winePDF 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_off0000b28e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB28E 16312 bytes
SHA-256: 4c769faeea402f78c11b38f6c4752dd42cfee8eaa6c2d8d553e65888a888d472
font_01_sfnt_off0000dba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA2 10608 bytes
SHA-256: 1118f8cced64cd68a4f163426b422e6d9fb4c20e5f0e68c5d4c234264bbd99b4
font_02_sfnt_off0000f3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1