Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c795e0ad8c75f68…

MALICIOUS

PDF

70.9 KB Created: 2021-09-16 12:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e403cd755a4a6545a41eb04bac545047 SHA-1: 134e97a1668d4d7e7ebb85da5deac9442c4b0a88 SHA-256: 5c795e0ad8c75f688c7b6581cab2bc07cb30b13878db28ffd26b2fa6e6a7f266
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, with critical and high severity firings. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also functions as a link farm, pointing to numerous disposable domains, suggesting an attempt to obscure the ultimate destination and evade detection. The presence of embedded URIs and the link farm behavior strongly indicate a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=roadrunner+for+android+by+delivery+hero PDF link annotation
    • https://vnmmalta.com/userfiles/file/bujiwisapoxat.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f43873a51b---ginofeferilojopozamulupun.pdfIn PDF document text
    • https://eniedu.com/data/file/20210914010259.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/49678812232.pdfIn PDF document text
    • https://manenshop.com/upload/files/70525308177.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/jagize.pdfIn PDF document text
    • https://santechnikosdarbai.lt/images/files/82137837694.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/kabazosadevumefolutomojor.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/34639482528.pdfIn PDF document text
    • http://kimhoatra.vn/upload/fckimagesfile/temujoxalajidufipawalun.pdfIn PDF document text
    • http://chinamakina.com/userfiles/file/45231539536.pdfIn PDF document text
    • http://namhungholdings.com/uploads/ckfinder/files/fiwas.pdfIn PDF document text
    • http://cardealer-space.com/js/upload/files/wufazo.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/riganipore.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/38676372531.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210907_153259.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/97550603893.pdfIn PDF document text
    • https://cupanghitam.com/contents/files/fujimuvokaribiresov.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/53243776595.pdfIn PDF document text
    • http://zenithmetals.com/files/30526658295.pdfIn PDF document text
    • https://vinasimex.com/uploads/file/tedoxe.pdfIn PDF document text
    • http://irollee.com/userfiles/file/wiparoj.pdfIn PDF document text
    • http://midoriku.zaitakunet.jp/app/webroot/upload_images/files/32118366826.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/kusosafa.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613d566344737---9248301115.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/4795712892.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/79972180920.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_off0000b50d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB50D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD24 10648 bytes
SHA-256: 33517546fd6953cd23cc758521db35ecda6b5aded0c067e749887207fd71b762
font_02_sfnt_off0000e569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE569 16096 bytes
SHA-256: ff7e201af901ef9471d92ae2811dccfb28779e23adba77a7351ba5748aaed143