Malicious PDF — malware analysis report

Static analysis result for SHA-256 f88dcf558d9f39e5…

MALICIOUS

PDF

81.8 KB Created: 2021-09-10 13:49:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2d58edf72bf3dbd9c6e58f3d8674066e SHA-1: befcb529ec87b8d126b87421a2ab2d721f201c01 SHA-256: f88dcf558d9f39e5262561d40b6c34c4c0b6ac80b1057cb5abb32ec9fb502368
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://irlanc.ru/uplcv?utm_term=android+delete+unused+apps PDF link annotation
    • http://streetnn.ru/data/upload/ck/files/dikuroguvaradonu.pdfIn PDF document text
    • https://rentcar888.com/uploads/files/202109012354417221.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/67960078697.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/84518421852.pdfIn PDF document text
    • http://celesteandtorsten.wedding/images/file/tujezusax.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f95a25b461---kudonisolitaluzamid.pdfIn PDF document text
    • http://finalbrand.cz/upload/file/davutafevunuxada.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/65590793599.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/zigos.pdfIn PDF document text
    • http://rayanchem.com/d/files/pazisepoxosexedodugo.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/bulabif.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374c55efa74---midoj.pdfIn PDF document text
    • http://taxiluzern.ch/khurasan/userfiles/files/disod.pdfIn PDF document text
    • http://laduses.nl/image/file/32992408800.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/xejivegimezin.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210905124232.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/duxuratezenen.pdfIn PDF document text
    • http://cdmvt.cz/sites/default/files/53680456810.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/7718824767.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/kaxunatudojikukiminiz.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/48524039725.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/wixopuzenulireluridemum.pdfIn PDF document text
    • http://fantacyhandicraft.com/userfiles/file/79384854308.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user//file/_0475030001630745196.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210906_083042.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/6357162608.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_off0000dd4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4E 10464 bytes
SHA-256: bdadd712fa32831d398a52f1f3495302a332054257d51558cd932d97817e29d9
font_01_sfnt_off0000f52b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52B 17212 bytes
SHA-256: 7bc74a75698364de9a8cb3117acdd551c5c2cb93e0f611b932994b762a8c9b36
font_02_sfnt_off00012183.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12183 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1