Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c85ec5f1eb5bb90…

MALICIOUS

PDF

107.5 KB Created: 2021-03-31 00:03:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: a5315933d1f97f1dd23e82bd8f6a1c32 SHA-1: 1587e84db9b8170dd8c806d603afa714a76057b7 SHA-256: 5c85ec5f1eb5bb9007c2c07e86081d26fe0bd1bd75048ffeaa99ea9d4abc4a78
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://pelibifir.ru/award?keyword=bernoulli+s+theorem+pdf+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4370275/normal_5fd6cd83744e9.pdfIn PDF document text
    • https://zisugopijelides.weebly.com/uploads/1/3/1/4/131438068/lozugoge-minavufunifuzew-domomexi-rotawuvosamuk.pdfIn PDF document text
    • https://cdn.sqhk.co/miloxuso/ijhbJMU/liverpool_echo_lfc_latest_transfer_news.pdfIn PDF document text
    • https://cdn.sqhk.co/sadirurafixi/igifOat/invasion_of_the_body_snatchers_1978_full_movie.pdfIn PDF document text
    • https://cdn.sqhk.co/besuduxikuvo/bjjIai7/xadux.pdfIn PDF document text
    • https://cdn.sqhk.co/tefegegesuxe/clnBeFr/43274287790.pdfIn PDF document text
    • http://veviwumifuvemuz.mypressonline.com/viewsonic_pjd5134_svga_projector.pdfIn PDF document text
    • https://cdn.sqhk.co/vizinifum/gjcQgjs/63961721561.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458145/normal_60055eef5d882.pdfIn PDF document text
    • https://cdn.sqhk.co/wabasenenem/fhfihih/pentimento_books_clinton_ms.pdfIn PDF document text
    • https://cdn.sqhk.co/xugiwatokax/gcjhgfU/23182177332.pdfIn PDF document text
    • https://xetudutadoboja.weebly.com/uploads/1/3/4/3/134344850/kedonub.pdfIn PDF document text
    • http://naturelofo.mypressonline.com/sherlock_holmes_download.pdfIn PDF document text
    • https://cdn.sqhk.co/jawutuwek/he8hed7/bitcoin_wallet_app_android_free_download.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450721/normal_60080a958c5d9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368976/normal_5fe161449821f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424985/normal_6061789cdb4b5.pdfIn PDF document text
    • https://cdn.sqhk.co/wadusazilox/mBhhwhe/roku_stick_replacement_remote_amazon.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gebetipuraxos.rf.gd/akeelah_and_the_bee_full_movie.pdfIn PDF document text
    • http://benepiro.rf.gd/brawl_stars_supercell_apk.pdfIn PDF document text
    • http://xoxekojut.onlinewebshop.net/84340118219.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://scripts.sil.org/OFLIn 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_off00014824.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14824 5424 bytes
SHA-256: f72aece0112c27dc0cdd4cf64e2d26d94b82347b04ee1b7fd6de10d0e1d81575
font_01_sfnt_off00015a7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A7B 13416 bytes
SHA-256: 77564287ab26e75f2772a689e64a3967306ca295131fa44675b1e5e4df4d5c0c
font_02_sfnt_off0001887e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1887E 16228 bytes
SHA-256: ce44bdfa90d14f5dadf5a6428bcd63046d6a267c33f4b5a62beb6f951b279b97