Malicious PDF — malware analysis report

Static analysis result for SHA-256 d85c9b85a1fdeb1e…

MALICIOUS

PDF

77.8 KB Created: 2021-09-20 13:29:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4ac5dfcf50c2158f23a70d1dd31f3926 SHA-1: facc5270c2bf38c31396ccb209bcaf288fcc225d SHA-256: d85c9b85a1fdeb1ecd80eb72059f828df641178023b1039db706e4cd603c5f2e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were extracted, the presence of many unknown URLs points towards a malicious redirection or download scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://www.cpiequipos.com/assets/images/user_files/files/jifexi.pdf In PDF document text
    • https://zlato-stribro-investice.com/upload/files/tinesafurosagolu.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/77834958554.pdfIn PDF document text
    • http://hakanhurdacilik.com/userfiles/file/zobutarim.pdfIn PDF document text
    • http://zssadkowice.pl/pliki/94299102510.pdfIn PDF document text
    • http://emirates-offshore.com/uploads/image/file/nagomebobenat.pdfIn PDF document text
    • https://benhgout.net/uploads/Files/file/18371996595.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/6646059897.pdfIn PDF document text
    • http://krzeptowski.pl/file/95172789102.pdfIn PDF document text
    • https://yodobashi-church.com/kuvoki.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/dozunanamepobapazer.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16137158a2f9cd---44748007733.pdfIn PDF document text
    • http://sualpturizm.com/userfiles/file/vawelezekiwe.pdfIn PDF document text
    • http://maginsaatmetal.com/resimlerfiles/bexas.pdfIn PDF document text
    • http://archiprojektai.lt/app/webroot/uploads/userfiles/files/32699540127.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091816585273.pdfIn PDF document text
    • http://energy-labels.com/userfiles/file/mumoxobaperele.pdfIn PDF document text
    • https://eirai.org/editor/ckfinder/userfiles/files/6489931400.pdfIn PDF document text
    • http://orenprom.com/img/account/file/60056953965.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/babexiwijivedubojan.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/65122494489.pdfIn PDF document text
    • http://modnyi-buket.ru/uploads/files/xepenujad.pdfIn PDF document text
    • http://capableapp.com/uploads/files/woguvonebimo.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/3741137185.pdfIn PDF document text
    • https://bahceneryaman.net/public/content-images/files/72253652137.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407b85a8172---bapasanuwexilosopakiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=operations+management+ebookPDF 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_off0000cc6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6E 10808 bytes
SHA-256: dec86419a88cd84f3ef10d73ea55048ddd58ac88658877931444692c4cbd70ae
font_01_sfnt_off0000e52b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3D 17072 bytes
SHA-256: f77dd10ac53e35aec5b8891f70cc2bd895e68d6b3242e2910ff3bf9c1a08a8e7