Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7acaa709bbb030e…

MALICIOUS

PDF

83.7 KB Created: 2021-09-20 08:11:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4639ac5cd4883b9847ce28dd2ed80834 SHA-1: adf10b9306755e45d851942b80f20f7e09a0c6c5 SHA-256: c7acaa709bbb030e9c573b91b24f486ba8bb097e4810178362ab83d18f20a2fc
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with several heuristics flagging it as a link farm on disposable hosting and pointing to algorithmically generated URLs. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://smidgel.ru/uplcv?utm_term=specimen+zero+free+game PDF link annotation
    • https://jeevadhara.org/work/london/userfiles/file/pifasonop.pdfIn PDF document text
    • http://dogomanhnghia.com/uploads/files/2548587045.pdfIn PDF document text
    • https://camelcarpet.org/d/files/79280536589.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b06c79cda7---96640756967.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/kolobinoposi.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/kinisaja.pdfIn PDF document text
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/kixesizemubebasowodonerun.pdfIn PDF document text
    • https://tinhhoaxanh.vn/userfiles/file/81020393849.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/debufexiduzu.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/96228240946.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/40362171661.pdfIn PDF document text
    • http://xn--12cfu9bc1efac9a9azfdsb7b9d1f0j.net/ckfinder/userfiles/files/95181256680.pdfIn PDF document text
    • http://take114.kr/FileData/ckfinder/files/20210915_F8B20CAD59286E50.pdfIn PDF document text
    • http://aurora-c.jp/files/files/59835636470.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2c4a2c162---84632635276.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/woxag.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/lopap.pdfIn PDF document text
    • http://massimosusto.eu/userfiles/files/54050816453.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/20167757500.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/48688123478.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/gufipomopanimuwufef.pdfIn PDF document text
    • http://laser-piskovani.cz/democms/userfiles/file/16549301546.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/pugokugubebubikivap.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109072157269424.pdfIn PDF document text
    • https://equimat-cheval.fr/file/61243100248.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_off0000df2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f741.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF741 10644 bytes
SHA-256: 64eba0b1f8fe95003445fb7082548bda4cb3f807c09788ccae36d473055037bd
font_02_sfnt_off00010fa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA2 19092 bytes
SHA-256: b12d9a4dbe31297c192fc5a77083743f8f85ae352ddf9a5bc0ae21993c774ec9