Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e50dbbb05bfe16e…

MALICIOUS

PDF

72.5 KB Created: 2021-09-17 00:15:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ec4de6d0f70ec5cc42365c16999dbad7 SHA-1: b51ce036d4f25069ba68eb1eab51ca6dff7c956b SHA-256: 4e50dbbb05bfe16edc75118b28cd1a49193a8004f774a5b26fea65e0993ce0dc
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs pointing to various domains, many of which appear to be link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=redmi+3+android+6 PDF link annotation
    • http://gostinica-domodedovo.ru/files/zigaw.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/50107858935.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142fcb44ff8b---bideduvotafiturotobimuna.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/sopolexorudukized.pdfIn PDF document text
    • https://portofcrotone.com/dati/upload/file/jijuxejudekokolem.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/pujumobatet.pdfIn PDF document text
    • http://epplast.com/files/file/7683028157.pdfIn PDF document text
    • http://dafangtour.com/fckeditor/userimages/file/68710759629.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/gosirasudazunowekanogaba.pdfIn PDF document text
    • http://atlonnuri.org/UpLoadImage/editer/files/8686350072.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d41994b9e9---xabukod.pdfIn PDF document text
    • https://egf.tw/test2/images/file/44656687771.pdfIn PDF document text
    • http://compagniaviaggi.gattinonimondodivacanze.it/themes/userfiles/files/lewizonetixuf.pdfIn PDF document text
    • https://1tlstar.com/storage/uploads/files/jibadofekeza.pdfIn PDF document text
    • http://xedaphcm.com/luutru/files/33674885173.pdfIn PDF document text
    • https://ukmalayalamnews.com/userfiles/file/70312717872.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/34147037296.pdfIn PDF document text
    • http://colantuono.it/userfiles/files/7095098837.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///motonazilokogudut.pdfIn PDF document text
    • https://electroagro.es/pub/files/debofotuwinorojozux.pdfIn PDF document text
    • http://interstroy96.ru/uploads/files/mutaronu.pdfIn PDF document text
    • https://vietrocknet.org/app/webroot/img/files/refizokiz.pdfIn PDF document text
    • https://grupo-kayros.com/userfiles/file/49939109217.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109020254029714.pdfIn PDF document text
    • https://vilus.cz/userfiles/file/34577324857.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_off0000b701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB701 18296 bytes
SHA-256: b70cf51294f19242d958aedccf08cb733c5f975f49d3f7b9e9a8675bf89dec0e
font_01_sfnt_off0000e4b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B1 10480 bytes
SHA-256: df8b2e07be6873cf7a0e55cca2bc670b4a16da3aed3224213cbf666ec2118e25
font_02_sfnt_off0000fc77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC77 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1