Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9b5650b2ac03abf…

MALICIOUS

PDF

72.9 KB Created: 2021-09-22 11:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7f86dafaf41e14ae18b50d12759e41b9 SHA-1: 712d9bfc83265acdef16de665beef4b6d4a80fec SHA-256: a9b5650b2ac03abf59349cc2be47451c3ebde3be1c49550e38076ebc13ceee8e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains a high number of embedded URLs, many of which point to disposable domains, indicating a link farm designed to obscure the true destination. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://wastran.ru/uplcv?utm_term=vidmate+low+version+apk+download PDF link annotation
    • http://xinyuemu.net/assets/202109/files/20210909224153787349.pdfIn PDF document text
    • https://areopag.ru/sites/default/files/uploads/10133073770.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/newezele.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/valifapolotugepupajov.pdfIn PDF document text
    • https://vhssirimpanam.org/ckfinder/userfiles/files/56495606645.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/karesesisa.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/doxugilufumilavunes.pdfIn PDF document text
    • http://bivalyracing.hu/files/file/30460690106.pdfIn PDF document text
    • https://songhong.info/userfiles/file/rexewogaxagopoxusov.pdfIn PDF document text
    • https://sarvodayasamaj.uk/upload/files/lasavoxazoxeduxi.pdfIn PDF document text
    • http://ristorantebiscione.com/userfiles/files/58060599992.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/poviketumorirexowaso.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145cde327173---vuvonafivav.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/juwalufaxavisaxejil.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/wikubekemodajaxofi.pdfIn PDF document text
    • http://ave-france.com/pics/files/76360497790.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/zurikapikotabepuwimaxi.pdfIn PDF document text
    • https://biholka.cz/uploades/userfiles/file/buvikuzejal.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/49039682342.pdfIn PDF document text
    • https://ncltandatbar.com/home/ncltandat/public_html/dowalumniusa/ckfinder/userfiles/files/xewoligiga.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161380d7872c58---55751186672.pdfIn PDF document text
    • https://cepatdaftargroup2.com/contents/files/tejegepapijopobuve.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/23879707542.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/79603332557.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_off0000bc73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC73 10768 bytes
SHA-256: 58f75b0505653f73e579b68be9b6e74ba1eb06eb01f7174406d2495911a0d6bb
font_01_sfnt_off0000d53b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53B 15992 bytes
SHA-256: 6118c90678813e67ef1b68a1c4a1ab7d4d09cc729d991e85e226aa06d0c31afc
font_02_sfnt_off0000fe06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1